Optimized the quadtree code a bit further
Optimized the quadtree code a bit further

avoid retraversing objects when not necessary

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