This shortcut does not work when the destination is a private node. We
also don't have this shortcut for regular payments. This commit
aligns the behavior between SendPayment and QueryRoutes.
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