Add ability to WorldTypes to display the 'Customize' button and react to it
Fixed render passes for EntityItems

Should be < instead of <=
Merge part of PR #375 related to ChunkEvent.Load for the client side
Merge branch 'master' of https://github.com/CovertJaguar/MinecraftForge into gh-updates
Merge branch 'worldtype_customize' of https://github.com/ExtrabiomesXL/forge into gh-updates