We need a record of the channel account before you start sending
payments through it. Normally we don't start allowing payments to be
sent until after the channel has locked in but zeroconf does away with
this assumption.
Instead we push out a "channel_proposed" event, which should only show
up for zeroconfs.
Any file in this directory which is executable and whose name only
consists of alphanumeric characters, space, '.', '-' or '_' will be
automatically loaded when lightningd starts (unless suppressed with
commandline options).