Patch update #2: Quality boost

What's new

• Added four new racing karts
• Added images of vehicles and spawn points to the UI
• Added a quality options panel (now you can change both the graphics quality and the precision of the physics simulation)
• Added more vehicle sounds
• Reorganized plots and added description tooltips

Bugfixes

• Improved the input system
• Meadow Environment: added fences around the map bounds
• Urban City: replaced obsolete road materials with new ones
• Fixed minor UI problems

Other

• Prepared code structure for vehicle modding (more information soon)