channeld can't do it any more: it's using local sockets. Connectd
can do it, and simply does it by type.
Amazingly, on my machine the timing change *always* caused
test_channel_receivable() to fail, due to a latent race.
Includes feedback from @cdecker.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>
Now connectd is doing the crypto, we can use normal wire io. We
create helper functions to clearly differentiate between "peer" comms
and intra-daemon comms though.
Signed-off-by: Rusty Russell <rusty@rustcorp.com.au>