server+peer: add 'init' message support

In this commit the support for global and local feature vectors were
added in 'server' and 'peer' structures respectively. Also with commit
additional logic was added and now node waits to receive 'init'
lnwire.Message before sending/responding on any other messages.

server.go

@@ -76,6 +76,14 @@ type server struct {
 	donePeers chan *peer
 	queries   chan interface{}
 
+	// globalFeatures feature vector which affects HTLCs and thus are also
+	// advertised to other nodes.
+	globalFeatures *lnwire.FeatureVector
+
+	// localFeatures is an feature vector which represent the features which
+	// only affect the protocol between these two nodes.
+	localFeatures *lnwire.FeatureVector
+
 	wg   sync.WaitGroup
 	quit chan struct{}
 }
@@ -129,6 +137,9 @@ func newServer(listenAddrs []string, notifier chainntnfs.ChainNotifier,
 		broadcastRequests: make(chan *broadcastReq),
 		sendRequests:      make(chan *sendReq),
 
+		globalFeatures: lnwire.NewFeatureVector(globalFeaturesMap),
+		localFeatures: lnwire.NewFeatureVector(localFeaturesMap),
+
 		queries: make(chan interface{}),
 		quit:    make(chan struct{}),
 	}
@@ -413,7 +424,11 @@ func (s *server) peerConnected(conn net.Conn, connReq *connmgr.ConnReq, inbound
 	// TODO(roasbeef): update IP address for link-node
 	//  * also mark last-seen, do it one single transaction?
 
-	peer.Start()
+	if err := peer.Start(); err != nil {
+		conn.Close()
+		return
+	}
+
 	s.newPeers <- peer
 }