Use correct lifecycle management for Proton objects

To reproduce this issue, set up a link route to a broker and set up a client that continually tries to create a receivers for non-existent queues on the broker

Please see attached reproducer client program and router config.

The problem seems to be that the proton library used by dispatch does not free links and sessions associated with open connections and so the memory keeps slowly building up. The links and sessions are freed when the connection is terminated.