Remove unnecessary engine releases within script engine lifetime
Merge branch 'master' of https://github.com/supertuxkart/stk-code into ScriptCache
Added basic caching for scripts
Don't allow to run locked tracks in random GPs
Don't allow doubled tracks in random GP.

Otherwise track number limit wouldn't have sense.
Make cascade split modifiable
Preparing lens flare branch
Add the lensflare shader
Add 'handicapped' to player name
Don't handicap AIs
Updated windows build instructions.
Updated GP for new mines track.
Fix #1665 (kart hovering in pyramid after jump) by only cushioning with
half the computed impulse.
Merge branch 'master' of github.com:supertuxkart/stk-code
Intro cutscene fixes
Fixed --camera-wheel-debug command line option (better distance
computation, no smoothing); removed unused function.
Prepare compute shader to stretch lightcoord
Implement depth histogram to position cascade split
Merge branch 'sdsm'
Merge branch 'master' of https://github.com/supertuxkart/stk-code into lensflare

Keep lens flare updated with master