lnrpc+routing: add edges and nodes restrictions to query routes

This commit allows the execution of QueryRoutes to be controlled using
lists of black-listed edges and nodes. Any path returned will not pass
through the edges and/or nodes on the list.

routing/router.go

@@ -1326,7 +1326,7 @@ func pathsToFeeSortedRoutes(source Vertex, paths [][]*channeldb.ChannelEdgePolic
 // route that will be ranked the highest is the one with the lowest cumulative
 // fee along the route.
 func (r *ChannelRouter) FindRoutes(target *btcec.PublicKey,
-	amt, feeLimit lnwire.MilliSatoshi, numPaths uint32,
+	amt lnwire.MilliSatoshi, restrictions *RestrictParams, numPaths uint32,
 	finalExpiry ...uint16) ([]*Route, error) {
 
 	var finalCLTVDelta uint16
@@ -1396,8 +1396,8 @@ func (r *ChannelRouter) FindRoutes(target *btcec.PublicKey,
 	// we'll execute our KSP algorithm to find the k-shortest paths from
 	// our source to the destination.
 	shortestPaths, err := findPaths(
-		tx, r.cfg.Graph, r.selfNode, target, amt, feeLimit, numPaths,
-		bandwidthHints,
+		tx, r.cfg.Graph, r.selfNode, target, amt, restrictions, 
+		numPaths, bandwidthHints,
 	)
 	if err != nil {
 		tx.Rollback()