Make use of window close and add another ESC keycode

[possibly-not]

HandleInput() returns 0 when receiving a window close request, this wasn't used before so the only way of closing the program was by pressing escape.

And getting on to the escape key, on my Linux machine keycode 65307 is the value for ESC so I added this to HandleKey As well I moved the keycode print so you can see the esc keycode before it quits.