Projectiles, Fullscreen, Units, Levels, etc.

Projectiles have been introduced.  They are at the most basic level of
function currently.  The window size has been changed to fullscreen
which will require future rework of the art assets and UI.  The entire
system for the unit differential between box2D, camera, and pixle units
have been fixed and optimized.  The two levels previously included have
been removed and replaced by a new level containing a new tileset.