- Add a third scenario that lets you drive around the maze.

- Made the RAM in scenario 2 the same as scenario 1, so you don't start the scenario with an "out of ram" warning.
- tweaked a spot on the maze grid where you should collide
I just wanted to make it "unlimited," but we don't have a value for that...  There's no way to reset the level, so when they run out they are forced to stop playing.  Maybe we should make it 1,000,000.