Fixed a lot of bugs and added a few new commands.
List of changes:
* Fixed team chat display names.
* Fixed players being set as a spectator when joining a game that's not in progress.
* Fixed player deaths and kills not being reset when the game starts.
* Fixed objectives not having proper display names.
* Fixed invalid number exceptions not displaying to the player.
* Fixed arrows damaging teammates.
* Added /siegeblocks, /setcore and /team commands.
* Added a temporary timer to keep spectators above 116y.
* Made the source code more pretty.