fullscreen, swim controls & animation notes

[vulture-boy]

New Updates:

• Added a full screen button
• Side icons now scale by screen size (also reordered them slightly)
• Fixed an issue where the overlay wasn’t aligned to the top left
• Sink / Float controls added (hold space bar and press W/S)
• Documentation and template now include the Animation component

There was a bug in A-Frame's core system related to the controls that limited movement in the vertical axis. I extracted the script and resolved the issue; our local copy has the fixed version and I’ve proposed a correction to the A-Frame repo: aframevr/aframe#5050 .