Safely handle ESC right before topping out

[gregorulm]

Gameplay is only recorded if the game tops out. However, it can easily happen that the player hits ESC a fraction before actually topping out. This means that no replay of the current game will be saved, which may not be intended. Thus, as a workaround, consider adding a delay, e.g. if the game is very close to topping out (check if the spawning next piece would collide with the stack as that's a game over), intercept the ESC keypress and then let the game top out before you allow the user to exit.