2.83.6
add Vehicles/Hinge2Vehicle demo, based on the ForkLift demo, using btHinge2Constraint with rigid body wheels change btHinge2Constraint to derive from new btGeneric6DofSpring2Constraint
fix some warnings, disable gimpact by default in world importer, use DIRECTLY_UPDATE_VELOCITY_DURING_SOLVER_ITERATIONS by default for now, until we find the issue with some failing test cases in btMultiBody fix a crashing issue in MyMultiBodyCreator.cpp (uninitialized variable) disable excessive debug printf in URDF2Bullet