This commit removes the `launchOutcome` and `shardResult` and uses
`attemptResult` instead. This struct is also used in `failAttempt` so we
can future distinguish critical vs non-critical errors when handling
HTLC attempts.
The routing package implements authentication+validation of channel
announcements, pruning of the channel graph, path finding within the network,
sending outgoing payments into the network and synchronizing new peers to our
channel graph state.
Installation and Updating
$ go get -u github.com/lightningnetwork/lnd/routing