This commit reverts cb4cd49dc8d3b0255afe9ff29af9c46c2dbb2c98 to bring
back the insufficient local balance failure.
Distinguishing betweeen this failure and a regular "no route" failure
prevents meaningless htlcs from being sent out.
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