Fixed issues with trackless mode.

Added custom blocks and made greys into grey blocks.
Added a post-processing glow effect to blocks, thrusters, water wake, and lane marker lines.

Reverted accidental color scheme change.

New glowy vehicle thruster style
Fixed cliff width
Fixed minor issue with shoulder lines visibility logic

Minor memory usage improvements
Minor tweaks to medium quality
Possible performance improvement (switched off sky light)
New "invert" and "tunnel" options, half-finished "shuffle_extra" option
Improved block positions when water is disabled

Fixed camera
Added options.shuffle
Fixed options.deterministic=false
Improved rings (preparing for trackless)
Improved wide track
Added trackless rail
Added minor options
Increased quality for people in medium quality mode
Tweaked skybox in medium and low quality

Fixed a water issue in Wakeboard mode.
Minor water improvement in some situations.
Minor lane/shoulder markers fix.

Major improvements to the background structure randomizer.
Fixed clouds showing through the end cookie.

Air particles fixed.