[ONOS-2096] Let GUI support tunnel
1. add a TunnelViewMesageHandler to handle message from the client.
2. add a tunnel view to show tunnel information on the GUI

Change-Id: I1d9a73c0e4e8ed1a55cdbef09426995989c4e76a
diff --git a/web/gui/src/main/webapp/index.html b/web/gui/src/main/webapp/index.html
index 4138e83..154f941 100644
--- a/web/gui/src/main/webapp/index.html
+++ b/web/gui/src/main/webapp/index.html
@@ -121,6 +121,7 @@
     <script src="app/view/app/app.js"></script>
     <script src="app/view/settings/settings.js"></script>
     <script src="app/view/cluster/cluster.js"></script>
+    <script src="app/view/tunnel/tunnel.js"></script>
 
     <!-- This is where contributed javascript will get injected -->
     <!-- {INJECTED-JAVASCRIPT-START} -->
@@ -138,6 +139,7 @@
     <link rel="stylesheet" href="app/view/app/app.css">
     <link rel="stylesheet" href="app/view/settings/settings.css">
     <link rel="stylesheet" href="app/view/cluster/cluster.css">
+    <link rel="stylesheet" href="app/view/tunnel/tunnel.css">
 
     <!-- This is where contributed stylesheets will get injected -->
     <!-- {INJECTED-STYLESHEETS-START} -->