refactoring plus pacman is now a circle and walls

Entity is now known as sprite and extends from pygame sprite object to
stay consistant with the pygame module.

Pacman is now drawn was a circle (eventually this will be a loaded,
animated image)

Added a wall class (collision detection to come)
Started to outline the collision detection model

^this^
Fixed the implementation of collision detection

works now!
Merge pull request #3 from MaddawgX9/collision-detection-(broken)

Collision detection (broken)
Refactored collision detection

-Refactored collision detection

-Removed package folders because they are not needed in python-style
design at the moment
Merge pull request #5 from MaddawgX9/Collision-Detection

Collision detection