#7 Responder (re)registration should replace topic interests

[Keith Flanagan]

Re-registration (pinging) of services doesn´t update topic interest registrations. This means that if you´ve got a responder under continued development (which sometimes involves changing which incoming topics it´s interested in), and you don´t drop the notification database between recompiles, then the new responder build will never be registered with its new set of interests.

Ensuring that existing subscriber topic interests get updated (replaced) at responder startup time would fix this.