Fixed a bug which caused the alien count to go wrong
ExplosionBehaviour and non gui part of Animation messages
Bug fixes for ExplosionBehaviour
Refactored Neighbourhood as an Interface as we may need different types of neighbourhood.
For example, the doughnut world of asteroids (both x and y axis loop back around), or the circular
worlds of some sideways scrollers.
Refactored collision strategy
Refactored CollisionStrategy part 2
Added Fragment (fragments a pose in random pieces), and used it in explosions.
Improved ExplosionBehaviour and Fragment
Used Jame's new setPixel instead of Fill in Fragment. Tinkered with the explosions.
Refactored
Refactored how Game is started, to allow Editor to be lauched from inside the game again.