DEMO Mario Kart: Ultra Circuit

[Kritter]

I've just updated the game to make the first track significantly wider and more forgiving, it probably shouldn't have been the skinniest and most corner-centric course at the very beginning.

Also tweaked the steering to be less sensitive, it wasn't as noticeable with a keyboard but with a controller it definitely is. I've made mushrooms last longer so they're more useful, and I've made going off the track a bit less punishing with the speed loss.