posterdown 1.0 CRAN Release

Initial CRAN Release

Updates

1. added posterdown_betterland and posterdown_betterport
2. added better support for multiple authors
3. added a simplistic way to control colour options
4. added wiki
5. added better support for tables
6. added support for blank posters
7. added support to render poster using no YAML options other than declaring the desired output.
8. removed all LaTeX templates, will no longer include LaTeX in future templates.

News

1. Lot's of changes have been made, the largest so far is the drop in support for LaTeX templates.
2. Lot's of examples have been added to the wiki showcase
3. Submitted package to CRAN!

Thanks to all who helped out and made suggestions!