Score and Levels

Hedgehog now progresses through "levels" when it completes the scene
Score and Level only reset when a new game begins
Seems to be working fine, haven't really tested it much though
From here it should be easy to add difficulty, then increase/decrease
hazard/food via difficulty :)

Also score is +10 for each food
+ time/10 (seems to average 200-300) on level completion