A_05

Lots of optimization!
* Wall tiles are now stored in a  2D array, array location must match
location in level
* Boundary check and blend wall methods have been updated to be much,
much faster
+ Particles can now loop a specified number of times (-1 for infinite)
* Some variables in player have been made public
*Dirt texture made slightly thinner to allow grass to flow over the edge

Previous update:
+ Dirt!
* Title of window updated from QVTN to SBG
* GameMenu now centers itself in the constructor
* Level now has proper depth values for its contents (including the
menu)
* Walls now set their bounds within the constructor
* the type variable for Walls has been made public