Lemming AI Improvements

Lemmings can now walk in any direction (not just left, right, forward,
back) and will face the direction they are walking in. Lemmings also
know what level they are on.

Started working on LemmingController, which will store all blocks that
have been climbed on and will be referred to by the lemmings when they
want to know where to go.

Removed obsolete files. Improved debug prints.