Deathball movement and animation fix.

Fix for the Deathball animation when moving vertically. Fix for slight warping when onTouchUp is called. Now uses VectorLen() to find the current velocity of the Deathball based on it's linearVelocityX and linearVelocityY.  Due to the value being more accurate, I also changed the divisor when setAnimationTimeScale is called to make the animation speed match.