Added beacon.
Exported the beacon.
Changed return type from GetPrimaryPotion() and GetSecondaryPotion()
Added beacon documentation.
Added beacon load/save.
Added window update.
Renamed functions and added beacon json saving.
Updated documentation.
Renamed "select..." methods to "set..." and better IsValidEffect() function.
Updated documentation again.
Use "default:" in switch.
Merge pull request #1269 from Howaner/BlockEntitys

Added beacon.