Added placement and interact handling for fence gates and trapdoors.
Fixed ShapedRecipe matching (fixes #465).
Fixed hoe interaction with coarse dirt and podzol.
Fire PlayerItemHeldEvent when players switch their held item.
Implemented remote console (rcon) support (closes #451).
Added support for player and mob heads.

Includes dandling for the skull item, block, and tile entity, as well as
lookup of profiles based on username for Bukkit support.
Implemented wall and standing banners.

Covers placement, tile entities, serialization, and sending the banners to
the client. Does not include crafting.
Add IBlockGrowable interface
Add ItemDye
Add BlockCocoa
Add BlockPlant
Add BlockCrops
Add BlockDoublePlant
Add BlockGrass
Add BlockMushroom
Add BlockSapling
Add BlockStem, remove BlockMelonStem and BlockPumpkinStem
Modify BlockTallGrass
Make random a protected static field of BlockType
Remove BlockPlant as it's not required here