Move IMaterialData into sub-package.
Move DyeColour into entity.data rather than entityData package.
Updated DyeColour class to provide transaction methods to and from Bukkit.
Move DyeColour from entity.data to data package.
Added TreeSpecies enum.
Added GrassSpecies enum.
Better ordering of methods inside TreeSpecies and DyeColour.
Added NetherWartsState enum.
Added SandstoneType enum.