Make a documentation for Bowling Plugin

[MrKangs]

While I am working on my galaga plugin tutorial, I do not think that I can cover advance topic. However, your bowling plugin has more feature that I believe it is worth documenting such as how to use the physics engine inside the plugin and etc.

[Exiled1]

The bowling example hasn't been ported to a plugin yet. I was planning on tackling physics engine integration after getting character controller stuff set up. However I'll be documenting it when I write it.