OpenArena Expanded Beta 52

New in Beta 52

Added gametype "Possession"
Added support for info files
Added the option of having doors that are only open during the active part of Elimination and CTF Elimination
The game no longer shuts down with "Could't find a spawn point" when a spawnpoint is missing.
Added ability to execute a script when the server is empty.
Code now compiles with gcc-4.8