LICENSE.txt

GNU GENERAL PUBLIC LICENSE

Version 3, 29 June 2007

Copyright © 2007 Free Software Foundation, Inc. <http://fsf.org/>

Everyone is permitted to copy and distribute verbatim copies of this license
document, but changing it is not allowed.

Preamble

The GNU General Public License is a free, copyleft license for software and
other kinds of works.

The licenses for most software and other practical works are designed to take
away your freedom to share and change the works. By contrast, the GNU General
Public License is intended to guarantee your freedom to share and change all
versions of a program--to make sure it remains free software for all its users.
We, the Free Software Foundation, use the GNU General Public License for most of
our software; it applies also to any other work released this way by its
authors. You can apply it to your programs, too.

When we speak of free software, we are referring to freedom, not price. Our
General Public Licenses are designed to make sure that you have the freedom to
distribute copies of free software (and charge for them if you wish), that you
receive source code or can get it if you want it, that you can change the
software or use pieces of it in new free programs, and that you know you can do
these things.

To protect your rights, we need to prevent others from denying you these rights
or asking you to surrender the rights. Therefore, you have certain
responsibilities if you distribute copies of the software, or if you modify it:
responsibilities to respect the freedom of others.

For example, if you distribute copies of such a program, whether gratis or for a
fee, you must pass on to the recipients the same freedoms that you received. You
must make sure that they, too, receive or can get the source code. And you must
show them these terms so they know their rights.

Developers that use the GNU GPL protect your rights with two steps: (1) assert
copyright on the software, and (2) offer you this License giving you legal
permission to copy, distribute and/or modify it.

For the developers' and authors' protection, the GPL clearly explains that there
is no warranty for this free software. For both users' and authors' sake, the
GPL requires that modified versions be marked as changed, so that their problems
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Some devices are designed to deny users access to install or run modified
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Finally, every program is threatened constantly by software patents. States
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render the program non-free.

The precise terms and conditions for copying, distribution and modification
follow.

TERMS AND CONDITIONS

0. Definitions. “This License” refers to version 3 of the GNU General Public
License.

“Copyright” also means copyright-like laws that apply to other kinds of works,
such as semiconductor masks.

“The Program” refers to any copyrightable work licensed under this License. Each
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To “modify” a work means to copy from or adapt all or part of the work in a
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The resulting work is called a “modified version” of the earlier work or a work
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A “covered work” means either the unmodified Program or a work based on the
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To “propagate” a work means to do anything with it that, without permission,
would make you directly or secondarily liable for infringement under applicable
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Propagation includes copying, distribution (with or without modification),
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To “convey” a work means any kind of propagation that enables other parties to
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An interactive user interface displays “Appropriate Legal Notices” to the extent
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1. Source Code. The “source code” for a work means the preferred form of the
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The Corresponding Source need not include anything that users can regenerate
automatically from other parts of the Corresponding Source.

The Corresponding Source for a work in source code form is that same work.

2. Basic Permissions. All rights granted under this License are granted for the
term of copyright on the Program, and are irrevocable provided the stated
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run the unmodified Program. The output from running a covered work is covered by
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You may make, run and propagate covered works that you do not convey, without
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When you convey a covered work, you waive any legal power to forbid
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a) Convey the object code in, or embodied in, a physical product (including a
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years and valid for as long as you offer spare parts or customer support for
that product model, to give anyone who possesses the object code either (1) a
copy of the Corresponding Source for all the software in the product that is
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“Installation Information” for a User Product means any methods, procedures,
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If you convey an object code work under this section in, or with, or
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ability to install modified object code on the User Product (for example, the
work has been installed in ROM).

The requirement to provide Installation Information does not include a
requirement to continue to provide support service, warranty, or updates for a
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Corresponding Source conveyed, and Installation Information provided, in accord
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implementation available to the public in source code form), and must require no
special password or key for unpacking, reading or copying.

7. Additional Terms. “Additional permissions” are terms that supplement the
terms of this License by making exceptions from one or more of its conditions.
Additional permissions that are applicable to the entire Program shall be
treated as though they were included in this License, to the extent that they
are valid under applicable law. If additional permissions apply only to part of
the Program, that part may be used separately under those permissions, but the
entire Program remains governed by this License without regard to the additional
permissions.

When you convey a copy of a covered work, you may at your option remove any
additional permissions from that copy, or from any part of it. (Additional
permissions may be written to require their own removal in certain cases when
you modify the work.) You may place additional permissions on material, added by
you to a covered work, for which you have or can give appropriate copyright
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Notwithstanding any other provision of this License, for material you add to a
covered work, you may (if authorized by the copyright holders of that material)
supplement the terms of this License with terms:

a) Disclaiming warranty or limiting liability differently from the terms of
sections 15 and 16 of this License; or b) Requiring preservation of specified
reasonable legal notices or author attributions in that material or in the
Appropriate Legal Notices displayed by works containing it; or c) Prohibiting
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Requiring indemnification of licensors and authors of that material by anyone
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contractual assumptions directly impose on those licensors and authors. All
other non-permissive additional terms are considered “further restrictions”
within the meaning of section 10. If the Program as you received it, or any part
of it, contains a notice stating that it is governed by this License along with
a term that is a further restriction, you may remove that term. If a license
document contains a further restriction but permits relicensing or conveying
under this License, you may add to a covered work material governed by the terms
of that license document, provided that the further restriction does not survive
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apply either way.

8. Termination. You may not propagate or modify a covered work except as
expressly provided under this License. Any attempt otherwise to propagate or
modify it is void, and will automatically terminate your rights under this
License (including any patent licenses granted under the third paragraph of
section 11).

However, if you cease all violation of this License, then your license from a
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the copyright holder explicitly and finally terminates your license, and (b)
permanently, if the copyright holder fails to notify you of the violation by
some reasonable means prior to 60 days after the cessation.

Moreover, your license from a particular copyright holder is reinstated
permanently if the copyright holder notifies you of the violation by some
reasonable means, this is the first time you have received notice of violation
of this License (for any work) from that copyright holder, and you cure the
violation prior to 30 days after your receipt of the notice.

Termination of your rights under this section does not terminate the licenses of
parties who have received copies or rights from you under this License. If your
rights have been terminated and not permanently reinstated, you do not qualify
to receive new licenses for the same material under section 10.

9. Acceptance Not Required for Having Copies. You are not required to accept
this License in order to receive or run a copy of the Program. Ancillary
propagation of a covered work occurring solely as a consequence of using
peer-to-peer transmission to receive a copy likewise does not require
acceptance. However, nothing other than this License grants you permission to
propagate or modify any covered work. These actions infringe copyright if you do
not accept this License. Therefore, by modifying or propagating a covered work,
you indicate your acceptance of this License to do so.

10. Automatic Licensing of Downstream Recipients. Each time you convey a covered
work, the recipient automatically receives a license from the original
licensors, to run, modify and propagate that work, subject to this License. You
are not responsible for enforcing compliance by third parties with this License.

An “entity transaction” is a transaction transferring control of an
organization, or substantially all assets of one, or subdividing an
organization, or merging organizations. If propagation of a covered work results
from an entity transaction, each party to that transaction who receives a copy
of the work also receives whatever licenses to the work the party's predecessor
in interest had or could give under the previous paragraph, plus a right to
possession of the Corresponding Source of the work from the predecessor in
interest, if the predecessor has it or can get it with reasonable efforts.

You may not impose any further restrictions on the exercise of the rights
granted or affirmed under this License. For example, you may not impose a
license fee, royalty, or other charge for exercise of rights granted under this
License, and you may not initiate litigation (including a cross-claim or
counterclaim in a lawsuit) alleging that any patent claim is infringed by
making, using, selling, offering for sale, or importing the Program or any
portion of it.

11. Patents. A “contributor” is a copyright holder who authorizes use under this
License of the Program or a work on which the Program is based. The work thus
licensed is called the contributor's “contributor version”.

A contributor's “essential patent claims” are all patent claims owned or
controlled by the contributor, whether already acquired or hereafter acquired,
that would be infringed by some manner, permitted by this License, of making,
using, or selling its contributor version, but do not include claims that would
be infringed only as a consequence of further modification of the contributor
version. For purposes of this definition, “control” includes the right to grant
patent sublicenses in a manner consistent with the requirements of this License.

Each contributor grants you a non-exclusive, worldwide, royalty-free patent
license under the contributor's essential patent claims, to make, use, sell,
offer for sale, import and otherwise run, modify and propagate the contents of
its contributor version.

In the following three paragraphs, a “patent license” is any express agreement
or commitment, however denominated, not to enforce a patent (such as an express
permission to practice a patent or covenant not to sue for patent infringement).
To “grant” such a patent license to a party means to make such an agreement or
commitment not to enforce a patent against the party.

If you convey a covered work, knowingly relying on a patent license, and the
Corresponding Source of the work is not available for anyone to copy, free of
charge and under the terms of this License, through a publicly available network
server or other readily accessible means, then you must either (1) cause the
Corresponding Source to be so available, or (2) arrange to deprive yourself of
the benefit of the patent license for this particular work, or (3) arrange, in a
manner consistent with the requirements of this License, to extend the patent
license to downstream recipients. “Knowingly relying” means you have actual
knowledge that, but for the patent license, your conveying the covered work in a
country, or your recipient's use of the covered work in a country, would
infringe one or more identifiable patents in that country that you have reason
to believe are valid.

If, pursuant to or in connection with a single transaction or arrangement, you
convey, or propagate by procuring conveyance of, a covered work, and grant a
patent license to some of the parties receiving the covered work authorizing
them to use, propagate, modify or convey a specific copy of the covered work,
then the patent license you grant is automatically extended to all recipients of
the covered work and works based on it.

A patent license is “discriminatory” if it does not include within the scope of
its coverage, prohibits the exercise of, or is conditioned on the non-exercise
of one or more of the rights that are specifically granted under this License.
You may not convey a covered work if you are a party to an arrangement with a
third party that is in the business of distributing software, under which you
make payment to the third party based on the extent of your activity of
conveying the work, and under which the third party grants, to any of the
parties who would receive the covered work from you, a discriminatory patent
license (a) in connection with copies of the covered work conveyed by you (or
copies made from those copies), or (b) primarily for and in connection with
specific products or compilations that contain the covered work, unless you
entered into that arrangement, or that patent license was granted, prior to 28
March 2007.

Nothing in this License shall be construed as excluding or limiting any implied
license or other defenses to infringement that may otherwise be available to you
under applicable patent law.

12. No Surrender of Others' Freedom. If conditions are imposed on you (whether
by court order, agreement or otherwise) that contradict the conditions of this
License, they do not excuse you from the conditions of this License. If you
cannot convey a covered work so as to satisfy simultaneously your obligations
under this License and any other pertinent obligations, then as a consequence
you may not convey it at all. For example, if you agree to terms that obligate
you to collect a royalty for further conveying from those to whom you convey the
Program, the only way you could satisfy both those terms and this License would
be to refrain entirely from conveying the Program.

13. Use with the GNU Affero General Public License. Notwithstanding any other
provision of this License, you have permission to link or combine any covered
work with a work licensed under version 3 of the GNU Affero General Public
License into a single combined work, and to convey the resulting work. The terms
of this License will continue to apply to the part which is the covered work,
but the special requirements of the GNU Affero General Public License, section
13, concerning interaction through a network will apply to the combination as
such.

14. Revised Versions of this License. The Free Software Foundation may publish
revised and/or new versions of the GNU General Public License from time to time.
Such new versions will be similar in spirit to the present version, but may
differ in detail to address new problems or concerns.

Each version is given a distinguishing version number. If the Program specifies
that a certain numbered version of the GNU General Public License “or any later
version” applies to it, you have the option of following the terms and
conditions either of that numbered version or of any later version published by
the Free Software Foundation. If the Program does not specify a version number
of the GNU General Public License, you may choose any version ever published by
the Free Software Foundation.

If the Program specifies that a proxy can decide which future versions of the
GNU General Public License can be used, that proxy's public statement of
acceptance of a version permanently authorizes you to choose that version for
the Program.

Later license versions may give you additional or different permissions.
However, no additional obligations are imposed on any author or copyright holder
as a result of your choosing to follow a later version.

15. Disclaimer of Warranty. THERE IS NO WARRANTY FOR THE PROGRAM, TO THE EXTENT
PERMITTED BY APPLICABLE LAW. EXCEPT WHEN OTHERWISE STATED IN WRITING THE
COPYRIGHT HOLDERS AND/OR OTHER PARTIES PROVIDE THE PROGRAM “AS IS” WITHOUT
WARRANTY OF ANY KIND, EITHER EXPRESSED OR IMPLIED, INCLUDING, BUT NOT LIMITED
TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
PURPOSE. THE ENTIRE RISK AS TO THE QUALITY AND PERFORMANCE OF THE PROGRAM IS
WITH YOU. SHOULD THE PROGRAM PROVE DEFECTIVE, YOU ASSUME THE COST OF ALL
NECESSARY SERVICING, REPAIR OR CORRECTION.

16. Limitation of Liability. IN NO EVENT UNLESS REQUIRED BY APPLICABLE LAW OR
AGREED TO IN WRITING WILL ANY COPYRIGHT HOLDER, OR ANY OTHER PARTY WHO MODIFIES
AND/OR CONVEYS THE PROGRAM AS PERMITTED ABOVE, BE LIABLE TO YOU FOR DAMAGES,
INCLUDING ANY GENERAL, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT
OF THE USE OR INABILITY TO USE THE PROGRAM (INCLUDING BUT NOT LIMITED TO LOSS OF
DATA OR DATA BEING RENDERED INACCURATE OR LOSSES SUSTAINED BY YOU OR THIRD
PARTIES OR A FAILURE OF THE PROGRAM TO OPERATE WITH ANY OTHER PROGRAMS), EVEN IF
SUCH HOLDER OR OTHER PARTY HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES.

17. Interpretation of Sections 15 and 16. If the disclaimer of warranty and
limitation of liability provided above cannot be given local legal effect
according to their terms, reviewing courts shall apply local law that most
closely approximates an absolute waiver of all civil liability in connection
with the Program, unless a warranty or assumption of liability accompanies a
copy of the Program in return for a fee.

END OF TERMS AND CONDITIONS