Fixed generation values not being written
Fixed piston being able to push water
Fixed ice creating a non-source block (still doesn't update though)
Removed problematic piston code
Also slightly refactored the variable / argument names (BlockID is deprecated, use BlockType instead)
git-svn-id: http://mc-server.googlecode.com/svn/trunk@921 0a769ca7-a7f5-676a-18bf-c427514a06d6
