GUI v1.0
- Abandoned the idea of reusing the GUI code from the practical, too f*cked up
- Restarted the GUI from scratch based on web tutorials:
http://www.ntu.edu.sg/home/ehchua/programming/java/JavaGame_TicTacToe.html
See 4.3 Sudoku
Now we have something that actually works!
- Have implemented a refresh() method that should later be called after each iteration to update the puzzle