Avahi optimisations

[Michael Stone]

>    * Minimize size of announced services (i.e. drop unnecessary data from TXT)
>      - The biggest item in the TXT of contacts is the key (which is BIG). But
>        this key is a requirement of bitfrost, so we can't get rid of it.

So far as I have been informed, the Bitfrost protections that would
require key transmission have not even been planned, let alone
implemented. Given that we think reducing mDNS bandwidth usage is a good
idea, does anyone see a real problem with dropping these keys until that
basic design work has been completed?

Michael