Fixed Physics component serializing velocity
Fixed Class not warning about lack of parent contructor calls when
the call was commented out
	modified:   public/scripts/engine/GameClass.js
	modified:   public/scripts/engine/GameEntityComponent_2DPhysics.js
Fixed networking of physics component, and rewrote part of the Class
system.
	modified:   public/scripts/GameLoader.js
	modified:   public/scripts/engine/GameClass.js
	modified:   public/scripts/engine/GameEntityComponent_2DPhysics.js