Add Random Block Ticking API.
Renamed methods in BlockType to be more mixin friendly.
Added GameRule API.
Capitalize PlayerChangeGameModeEvent
Fix import in World
Merge pull request #279 from SpongePowered/feature/random-tick

Add Random Block Ticking API.
Fix minor javadoc issues and inconsistencies. Fix misspelling in BiomeTypes.
PlayerInteractEvent always returns a block.