Fixed shadow balls not spawning particles on entity hit.

Also, they no longer collide with entities. It's not a bug, it's a
feature!
They also cause short blindness. That is a bug, not a feature. But it's
a bug I won't fix!
Shadow ball damage scales much more aggressively with radius.

Also cleaned up superfluous code in there.
Hackishly fixed some IaSServerCommand hiccups in multiplayer.