Adding title and taking care of -Wall errors

Added the title "Tictactoe" on top of the board and made miscellaneous
changes to fix some warnings brought on by -Wall.
Changed use of 0, 1, 2, 3 for Tic and SuperTic

The Tictactoe and SuperTictactoe modules had a "play the game" function
which took Int arguments of 0, 1, 2, 3 to play the game. This was more
elegantly solved by creating a separate GameType type which is then fed
to the function.