Define a new GraphSource interface required by the invoicerpc server and
remove its access to the graphdb.ChannelGraph pointer. Add the new
invoicesrpc.GraphSource interface to the GraphSource interface
and let DBSource implement it.
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