Keyboard support for the Video Player

Space bar toggles play/pause. Right and Left Arrow keys seek the video forwards and back. Up and Down Arrow keys increase and decrease the volume. M key toggles mute/unmute. F key toggles fullscreen off and on. Double-clicking with the mouse toggles fullscreen off and on. Number keys from 0-9 skip to a percentage of the video. 0 is 0% and 9 is 90%.