Are zeroconf advertisement methods using stream still useful?

Created by: stephanemagnenat

By fixing #692 (closed), I realised that the methods of Zeroconf taking a Dashel::Stream*, such as void advertise(const std::string & name, const Dashel::Stream * stream, const TxtRecord & txtrec); or void forget(const std::string & name, const Dashel::Stream * stream), are just calling the equivalent method taking a int port as parameter. In this context, I am not sure they are useful, and make the API of Zeroconf larger.

@davidjsherman, what do you think?