This is in line with the warnings draft, where all-zeroes in a
channel_id is no longer special (i.e. it will be ignored).
But gossipd would send these if it got upset with us, so it's best
practice to ignore them for now anyway.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Changelog-Added: Protocol: we treat error messages from peer which refer to "all channels" as warnings, not errors.
`openchannel_signed` and `openchannel_update` which allow a user to
continue a openchannel or kick off the completion of a openchannel.
`openchannel_update` should be called until it returns with
`commitments_secured`.
