Fix tile entities: furnaces clearing, machine orientation. Fixes #650.

Vanilla (stone) furnaces would kick the player out of the GUI as
smelting begun, and clear all items on open. IC2 machines would
always face downwards on placement. Probably many other issues.
All caused by a broken setBlockTileEntity() / removeBlockTileEntity().

To fix this, we properly merge Forge's changes to these methods.
The bad merge was introduced in the 1.5.1 update. After restoring
the methods, tile entities place correctly.