12.3.0

• Bugfix: invalid contact points for heightfield/mesh shapes (Minie issue #18)
• Bugfix: unsafe normalize() is used in btRaycastVehicle
• Bugfix: logic errors in btTriangleShape::isInside()
• add a to the CollisionShape class to disable contact filtering
• identify native libraries built with DEBUG_PERSISTENCY defined
• add accessors to the CollisionSpace class for deterministic overlapping pairs