Remove use of inheritance
Remove use of inheritance

Moved from an inheritance based use of Swing to a pattern using containment,
in order to keep the outward behaviour of the class simpler.

dnhckt/GameArena,madinsane/Dodgeball,AngieChandler/BallEater,Mark-McE/GameArena,dnhckt/GameArena,dnhckt/GameArena,Luthor18/TestPost