Memory: As an end-user, I want to be able to play a game of memory

• The user should be able to decide what style of game to play, minimum support: 4x4, 4x2, and 2x2.
• The player has to be able to flip the tiles with the mouse and keyboard.
• The player must only be able to flip two tiles face up at a time.
• After a suitable time, matching tiles that face up must not have a visible representation in the grid.
• After an appropriate time, tiles facing up and not matching must be flipped face down.
• The positions, or rather the images, of the tiles in the grid must be randomized before each game round.
• Throughout a game round, the tiles must retain their original positions in the grid.
• The game must count how many attempts the player has made to find matching tiles and present the number of attempts when the game round is over.
• After a game round is over, the user must be allowed to start a new game round without having to start a new sub-app.

For hint and boilerplate code see: Exercise - Memory Game