If we have an address hint, we start with that, but we'll use
node_announcement information if required.
Note: we (ab)use the address hint when restoring from the database
or reconnecting, even if the connection was *incoming*. That meant
that the recipient of a connection would *never* manage to connect out.
We still don't take multiple addresses from the DNS seeds: I assume we
should, since there could be IPv4 and IPv6.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
4f1186c4b1