[#538] almost working collisionAngle
[#538] almost working collisionAngle

also fixed the `angleTo` and `angleToPoint` functions

gopalindians/melonJS,MarkoIvanetic/melonJS,srbala/melonJS,TukekeSoft/melonJS,srbala/melonJS,gopalindians/melonJS,gopalindians/melonJS,TukekeSoft/melonJS,MarkoIvanetic/melonJS,srbala/melonJS,melonjs/melonJS,melonjs/melonJS,rlugojr/melonJS,rlugojr/melonJS,TukekeSoft/melonJS,rlugojr/melonJS