v0.95

Reworked 'behavior' system. Removed behavior class and replaced with
enum list in BaseObject. Moved interacting/use timer code out of
BaseObject and into Player. CraneObject now inherits from LevelObject so
that a visible object in the game can represent a crane and intuitively
hold the behaviors associated with interacting with it. Cleaned up
player code. Held objects are no longer visible while being held.
Started player character design.