Added database object and merged in AI branch

Added database object called DatabaseHelper. Use the namespace Database
to use it. Merged the dev branch with the AI branch.
Joe, I almost have the game over method in Form1:
gameOver(int[] winningPattern, char winningPiece);
Also, I am almost done with the game over method in the database object:
score(Player player_one, Player player_two, char who_won);