Mark all channels as syncing when we connect to our uplink. They will
finish syncing later when the uplink syncs. Normally the channel state
is fully synced here anyway, except if we do not know the modes the
uplink has yet.

Also fix a related issue with resetting chanels and bouncing modes on
our clients, if this is done prior to knowing which modes exist it would
silently fail.
m_ssl_gnutls: Fix deprecation warnings when using newer GnuTLS versions.
Update the dutch language file.
cs_set_misc: Add missing override capability for services operators, and logging.
Show a better log message when disconnecting from the uplink