whoah, a new update!

Update time!

Main changes:
- Updated Unity Engine
- Fixed a problem, which led to poor performance on Hard Track
- Brought back missing camera effect

Music:
- Fixed a bug with music randomisation, which led to always playing one song on Hard Track
- Changed audio streaming method to improve performance

UI:
- Adjusted UI to make it fit better on various aspect ratios

Hard Track:
- Added missing colliders on crashed trucks