Update #7 - Major system changes

Changes include: - A fix for invisible asteroids (should no longer spawn) - Adjusted size of the mouse cursor to be a bit smaller - Improved performance again which should help lower end devices more, this does not affect higher end devices that much - Adjusted the way asteroids spawn, you can no longer move straight in a diagonal direction and collect resources easily, now it's more dynamic but I also made it so that sometimes there will be a lucky patch of asteroids all clumped up together which should help make it more satisfying