Updated particle explosions so that they more or less cone out from
their source in the direction of the object's velocity

+ I also added some color, I figure particles could be the only things
with color
Changed asteroids into polygons that lose sides as they're hit, still
degenerating into two smaller polygons with fewer sides

+ Also updated some of the generation for the smaller satellites so that
they move away from the center of the blast they spawned from.
-- It's not working right