Bug in update sql string creation for NodeNeighbour table
Raise a message to Info level to clearly indicate successful connection
and tidy up another log message
When an endpoint is lost we should set that neighbour to unavailable in
the registry
eclipse launcher uses build in fabric.build project
Neighbours marked unavailable due to MQTT issues must be removed from
the Discovery cache to enable rediscovery and reconnection attempts.
Discovery Listeners copig with connection failure, trying to restablish
at regular intervals  at regular intervals
Change a default timeout value