Mouse support and minor fixes

The keyboard inputs are also available for Race and Shooter modes and the game can run without the use of VR using a Mouse to see around, note that this is only available as a fallback when no VR device is detected.
Some fixes was also made on this version:

1. Graphic settings are now working as expected.
   
2. Twilight bugs were fixed.
   
3. Lost Forest is running a little bit faster, specially on Medium quality.
   
4. Leaderboard user's images have the correct scale now.