Added btGeneric6DofSpringConstraint and linear/angular limits to btGeneric6DofConstraint.
Added getBreakingImpulseThreshold and setBreakingImpulseThreshold to btTypedConstraint.
btGeneric6DofConstraint implements btTypedConstraint
Style correction.
Added btContactSolverInfo and getSolverInfo to btDynamicsWorld.
Added getNumConstraintRefs and getConstraintRef to btRigidBody, removeAction to btDynamicsWorld and getCurrentSpeedKmHour to btRaycastVehicle.