Forgot to remove calls in WorldIO to object streams. Replaces them when
basic file streams and added Save method to EncodedWorld.
Fixed issues regarding hazards and conveyers not properly storing their
id in Tile.

Tested loading saving worlds with multiple hazard types, conveyers,
block types, sprites, bonzo placements, and everything appears to be
saving and restoring properly.

It's done. The new save file format. Levels can now be created without
fear of them breaking when new stuff is added.