Refactored a little, AISprites now keep track of where their state changed
Refactor away from '== null' checks towards isSet
AISprite turn faster or slower in turnUnseenDirection depending on state
AI Sprite's path_tween speed should match their movement state for that tween
Fix #25 (for real this time)
#3 : Hunting behavior partially implemented, character wanders around inside a box looking for the player. Needs to stop/turn, and for some reason the state never ends.