Also, we split the more sophisticated json_add helpers to avoid pulling in
everything into lightning-cli, and unify the routines to print struct
short_channel_id (it's ':', not '/' too).
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
If type and tag match, then we replace any existing message in the
queue. This allows us to drop old announcements. Special care needs to
be taken so that dependent messages are not reordered, but for gossip
this is the case, since the `channel_announcement` cannot be updated.
Moved the broadcast functionality to broadcast.[ch]. So far this
includes only the enqueuing side of broadcasts, the dequeuing and
actual push to the peer is daemon dependent. This also adds the
broadcast_state to the routing_state and the last broadcast index to
the peer for the legacy daemon.
