This commit makes the outgoing link pipeline the settle to the
switch as soon as it receives it. Previously, it would wait for a
revocation before sending it, which caused increased latency on
payments as well as possibly never settling on the incoming link.
A duplicate settle is still sent to the switch, but it is handled
gracefully. A new AckEventTicker was added to the switch which
acknowledges any pending settle / fail entries in an outgoing
link's fwd pkgs in batch. This was needed in order to reduce the
number of db txn's which would have been incurred by acking whenever
we receive a duplicate settle without batching.
This flake was caused by the rpcserver receiving a CloseChannel request
before Alice's channel event subscription request, causing Alice to miss one
notification. As a result, we move Alice's subscription to the beginning of the
test.
Additionally, we add a check to ensure the opening notifications are
received in the right order.
Earlier versions of ListPayments only included completed payments. We
return to this behavior by ignore all other payments if the nonSucceeded
boolean is not set in the request.
testHoldInvoicePersistence tests that a sender to a hold-invoice, can be
restarted before the payment gets settled, and still be able to receive
the preimage.
Previously every payment had its own local mission control state which
was in effect only for that payment. In this commit most of the local
state is removed and payments all tap into the global mission control
probability estimator.
Furthermore the decay time of pruned edges and nodes is extended, so
that observations about the network can better benefit future payment
processes.
Last, the probability function is transformed from a binary output to a
gradual curve, allowing for a better trade off between candidate routes.
