Added app icons
Merge branch 'TicTacToe_Backend' of /Users/michaelcoombs/AndroidStudioProjects/YCPGamesProject with conflicts.
Merge remote-tracking branch 'origin/TicTacToe_Backend' into TicTacToe_Backend
Added view background and buttons to xml layout, began adding code to buttons to modify game
Added base code for buttons and mUpdateView() to be called by onClickListener
Fixed nullPointerError, continued button work