This adds one new feature, that discovery servers can have ?nolookup to
be used only for announces. The default set of discovery servers is
changed to:
- discovery.s.n used for lookups. This is dual stack load balanced over
all discovery servers, and returns both IPv4 and IPV6 results when they
exist.
- discovery-v4.s.n used for announces. This has IPv4 addresses only and
the discovery servers will update the unspecified address with the IPv4
source address, as usual.
- discovery-v6.s.n which is exactly the same for IPv6.
GitHub-Pull-Request: https://github.com/syncthing/syncthing/pull/4647