Chunky Orbits updated - new movement method

I've added a new option for moving around the Chunky Orbits sim. It's very similar to classic first person shooter controls. You can move with the left touchpad or thumbstick, and rotate with the right. Modify your direction by pointing your left hand. Press in on the pad/stick to move faster.

I still like the funky 'accordian' stlye movement from previous versions, but several users have requested something a little more familiar. You can use either method, they are both available at all times. 

Other changes include some small adjustments to the main menu and an update to Unity engine v 5.6. See the ChangeLog for the full list. 

Thanks to everyeon who's supporting my indie dev efforts by buying my stuff! Please let me know if I broke anything.