Added Draw Orders (Incomplete)

-Added drawDepth (float) to sprite base class.  This value defaults to
0.5 and ranges between 0 and 1.  Sprites with a higher number are drawn
on top of sprites with a lower value.
-Added depth(float) method to sprite base class.
-Changed back to a single spriteManager in an attempt at draw order.  I
think I was drunk before.
-Corrected map naming qualifications after changing sprite lists back to
spriteManager.
-Updated sprite base draw with new method for layer depth.
-Made map a static class becuase there is only one and needed access
from within Player class.
-Added getHeight() to map class that simply returns the Y viewing
position (position of player?)
-Updated the overridden draw method for AnimatedSprites.
-Added automatic calculation for draw layers for static sprites
(incomplete, Map needs updating).