Track rebalances, and report income events for them.
Previously `listincome` would report:
- invoice event, debit, outgoing channel
- invoice_fee event, debit, outgoing channel
- invoice event, credit, inbound channel
Now reports:
- rebalance_fee, debit, outgoing channel
(same value as invoice_fee above)
Note: only applies on channel events; if a rebalance falls to chain
we'll use the older style of accounting.
Changelog-None
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).