The Unvanquished Master Server Requires Python 2.6

Protocol for this is pretty simple. Accepted incoming messages:

• 'heartbeat \n' is ignored for the time being (it's always Unvanquished in any case). It's a request from a server for the master to start tracking it and reporting it to clients. Usually the master will verify the server before accepting it into the server list.
• 'getservers [empty] [full]' A request from the client to send the list of servers.
• 'getserversExt [ipv4|ipv6|dual] [empty] [full]' A request from the client to send the list of servers. 'dual' requests that info about which are dual-stack is also returned.