Event Listener game

Let's play with some event listeners! Thanks to Nitya_Juni, we can enjoy experimenting with different event listeners by playing the “Event Listener Game”. Before running the game for the first time, look at lines 61 through 70 to see the different event listeners that have been set up. For example, on line 65 we see `screen.onkey(DrawSquare,"s")`, this means that when you press the letter s on your keyboard, the turtle will draw a square! Test all of the commands to check out the cool drawings that you can make!