Lots of stuff

-Rewrote the way mouse clicks are handled to make it much more reliable.
-Made the game scalable, doesn't scale as I would like it to much to
blurry.
-Fixed mouse issue with scaling.
-Switched pieces to sprite sheets and have direction now.
-Changed the way units are loaded into the game to allow for different
maps/arenas to be loaded in with ease.
-Added a very basic header to show whose turn it is.
-Cleaned up Arena files to make more readable.  Also fixed up Arena2
using the wrong tiles.
-Changed the way margins are calculated to allow for arenas with
different margins on different sides.