Added ship explosions
Added bomb functionality

We now have a working bomb object.

It is currently overriding the shoot behavior so it's not using the
missle.  We need to add another button so we can shoot them seperately.
Updated the bomb explosion animation

By making the size of a single frame of the animation larger in
increases the overall AOE size of the bomb.
Updated the AOE size for the bomb
bomb is now fired with B and lasers are fired by spacebar
Merge pull request #44 from otternq/dev-shipExplosion

closes #40 Dev ship explosion