[x] proper game loop (almost) [x] move the head of the snake in a straight line [x] move the head of the snake with keyboard
[x] make game loop setInterval better [x] kill the snake if out ouf bound [x] kill the snake if eat itself [x] dont apply direction change if its oppostive to direction
[] refacto and test all the things! [] double buffering [] dont spawn cherry on snake [] frame rate ctr in top left corder