Added fill shot
added a getLinearHeightMapPoint() method
nothing actually
made animationLimit and animationStep a passed in argument instead of
hardcoded
Merge branch 'master' into ZachBranch
added gravity and terminal velocity values. Also implemented impulse
driven movement
Added movement, turn identification and switching, made range finding
and collision methods general, and shooting
added methods to initialize tanks
Set up turn switching. Tanks now move and shoot with space bar. Game
crashes when out of ammo, this is a known error.