The `init_featurebits` are computed at startup, and then cached
indefinitely. They are then used whenever a new `init` handshake is performed.
We could add a new message to push updates to `connectd` whenever a plugin is
added or removed, but that's up for discussion.
I tried to just do gossipd, but it was uncontainable, so this ended up being
a complete sweep.
We didn't get much space saving in gossipd, even though we should save
24 bytes per node.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
connectd is the only user of the cryptomsg async APIs; better to
open-code it here. We need to expose a little from cryptomsg(),
but we remove the 'struct peer' entirely from connectd.
One trick is that we still need to defer telling lightningd when a
peer reconnects (until it tells us the old one is disconnected). So
now we generate the message for lightningd and send it once we're woken.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>