Added simple script that makes all challenges trivial
(0 laps, no time or energy limit).
Merge remote-tracking branch 'upstream/master'
Test commit.
Fixed format for TODO file.
More testing.
Fixed typo in warning message.
Simplify code for checking best refresh rate on linux, which I added previously.
Fixed accidentaly noticed typo in comment
Merge branch 'master' of github.com:supertuxkart/stk-code
Merge branch 'master' of github.com:supertuxkart/stk-code
Adjust graphical offset by rotation to fix graphical position not exactly
the same as physicsl position when kart drives on wall.
Fixed --track command line option.
Fix for GL 3.1 context
Fixed compilation error
Interpolate the normal for the gravity to allow smoother changes of
gravity - though it does not improve the bumpiness on twisted road section.
Some cleanups
Use fixed attribute location for instanced objects.
Some cleanup
Clean vao_shadow_pass on instanced.
Change power of bouncy edges in soccer field as temporary solution for #1367.

Ideally power of bounce should depend on soccer ball weight.