Support in registerListener() to handle listening on own UUri

[PLeVasseur]

I think in registerListener() we should be explicitly handling things differently depending on whether the UUri we're given describes a RPC Request or a Response.

If you'd like, you can take a look at how this is done in up-client-zenoh-rust

Note the Response message section on #38. I thought it a good idea how in the Rust implementation we ensure that we have a Response callback registered.