Re-committed all changes!

Fixed:
 + Moved the unnecessary setup call to the constructor instead of explicit demand a call when creating an instance of the Animation and Entity classes.

Added
 + Simple tile set
 + Simple level generator that reads a text file for generating levels


Needs to be moved:
 + The collision detection of pacman vs level should be moved somewhere other than pacman class

Urgent todo:
 + Make support for scaling when rendering (the collision detection will not recognize scales as is now)
 + Ghost entity in Pacman (currently it loads the pacman spritesheet)