LOTS OF CHANGES

TONS of small coding changes!
Look around and you'll see them.  I would try and make things more
efficient wherever possible.

-Updated menus!
-FULLY implemented AI  with 4 difficulties!
-unfinished 'end game' funtionality.
-Fixed text (Which changed the pause screen text)
-Renamed some variables (for better descriptions)
-Wow I added about 200 lines of code!
- Just look around and you'll see all the stuff I added

(I left a bunch of comments for you in 'onUpdate')

Still a bunch of bugs!
__TOP-PRIORITY__
-fix the game so if you press the close button (top-right 'X') it
actually closes the program.
-The paddles don't hit the ball in the right direction and it seems
really bad now.

__Lower priorty__
- ......TONS!!!!