Minimum framerate and death animations.
I capped the minimum framerate at 20 fps.  Also added death animation stops to sprites, as well as code in the appropriate mooks/scenes to not remove the entities until after the death animation has played.  This will hopefully really come in handy for the mountain assault and space scenes later.  (That's right.  Space scene.)  Also removed a lot of zeroes from Sprites where animation stops were irrelevant anyways.