Pull Request now includes Tetris!

completed: warmups
tower of Hanoi (with saving via YAML)
Mastermind(no saving, but yes AI)

Single block Tetris, with high scores saved, plus a difficulty setting as well. (Boring under about level 8).
This works just fine, but would fail if you had an intentionally malicious user who entered in "-5".  Maybe validate on whether digits == 0, 1, or anything greater than one just to be safe