Wrapper class for rigid body deletion notifications.
The RigidBodyDeletionNotification class is a wrapper class for marshaling and unmarshaling rigid body deletion notifications. When receiving a deletion notification this indicates that the body was deleted (e.g. due to outflow or manual deletion). Thus the shadow copy is no longer valid and must be removed from the receiving process. A deletion notice must only be sent by the owner to a receiver having a shadow copy of the concerned body. On deletion attachments to other bodies must be detached.