Add btCollisionObject::setIgnoreCollisionCheck to disable collisions between specific instances, without having a btTypedConstraint. See https://github.com/bulletphysics/bullet3/issues/165
Make btMultiBody and btMultiBodyJointMotor backwards compatible with Bullet 2.82 API (single-DOF API)
Use statically linked freeglut, instead of dynamic glut for the obsolete Bullet 2.x demos
Add the 'reset' method to b3GpuDynamicsWorld, and use it in the BasicGpuDemo (pretty slow in debug mode, use release mode)
Don't crash in btCollisionWorld, if there is no collision dispatcher