Update anonymous relay to use a target with null address in line with Addressing spec direction. Relies on update to broker to enable support. Needs finishing.
add support to test peer for refusing producer links
encapsulate the endpoint field
add test of behaviour when link is refused, i.e null source in attach response
add incomplete test of anonymous producer behaviour when the anonymous-relay node is not supported
verify a non-null terminus during producer open completion, fail if otherwise
temporarily disable the tests that fail due to requiring an outstanding patch to broker side anonymous relay behaviour