the mines can be hidden, so I have a janky
workaround. You might have to try moving the
cursor multiple times but at least now it actually
works. Next step, add flagging!!!!
if the cursor is over the mine. We now have to
not end the game until the user SELECTS the space
the mine is at. I hadn't realized that is_empty
only works if display is True? So I moved the
game.end() to the mine class.