U3L3-Tic-Tac-Toe

11-8-21: Ideas for future improvement

1. Computer should detect who wins 
2. User Interface - manage the game like congratulations and next moves.
3. Costumes/Backgrounds
4. Scoreboard
5. Computer Player

11-17-21: Fixed bug related to playing squares that have already been played.

11-19-21: Game now detects wins and ties, and it stops the game when this occurs.
We need to look for repetitive code to find opportunities for abstraction.