Changes:
- World generation related optimizations: disabled autosave, pre-generation will now stop when the game starts (even if unfinished), arena will remain in 'ending' phase during spawn generation, spawns will no longer be generated if arena is inactive
- Added /t command for team chat
- Added configurable rewards for players who lost
- Disabled friendly fire for team members
- Added configurable world game rules
- Fixed players being able to place and use portals