Restore some 1.7.10 behaviour (+ some things)

-Ocelots will sit on chests
-Chests won't open if there's a solid block on top of it
-Obsidian chest is explosion resistant
-Fixed getDrops
-Chests are rotatable again
-No more direct GL calls

Also:
-Cleaned up a bunch of imports and unused fields
-Chests now render the breaking animation.
-Disabled face culling for crystal chests (makes them look cooler:3)