Work on shatter ice effect
Fix shattered state transition errors
Tweak fragment velocity upon shatter.

Still need to modify collision detection (and ApplyImpact/ApplyForce)
to handle shattered case (check fragments rather than unit - make sure old
unit location doesn't collide).
Also need to make shattered units eventually respawn.
Updates should reduce fragment duration and fragments should be eat-able
by black hole (and should respond to gravity).
Fix fragment rotation error
Tweak ice shatter visual effect
Work on ice gravity effects
Increase fragment eat rate
decrease fragment scale factor
clamp fragment velocity
Fix ice fragment gravity response
Implement fire effect panic
Merge branch 'stat-effect-combos'