GUI -- Added updateDevice event handling.
 - Display offline devices as grey.
 - Tracing web socket messages (for now, in console; in future, to trace view).
 - Captured sample events for use with test scenarios - both from and to the server.
 - Added description to scenario file.

Change-Id: I7825b32d63496ebea2ab5789519fb0c6af6c5257
diff --git a/web/gui/src/main/webapp/topo2.css b/web/gui/src/main/webapp/topo2.css
index acd0bc9..6c0c313 100644
--- a/web/gui/src/main/webapp/topo2.css
+++ b/web/gui/src/main/webapp/topo2.css
@@ -41,11 +41,16 @@
     stroke: #ccc;
 }
 
-#topo svg .node.device.switch {
+/* note: device is offline without the 'online' class */
+#topo svg .node.device {
+    fill: #777;
+}
+
+#topo svg .node.device.switch.online {
     fill: #17f;
 }
 
-#topo svg .node.device.roadm {
+#topo svg .node.device.roadm.online {
     fill: #03c;
 }
 
@@ -53,12 +58,17 @@
     fill: #846;
 }
 
+/* note: device is offline without the 'online' class */
 #topo svg .node.device text {
-    fill: white;
+    fill: #aaa;
     font: 10pt sans-serif;
     pointer-events: none;
 }
 
+#topo svg .node.device.online text {
+    fill: white;
+}
+
 #topo svg .node.host text {
     fill: #846;
     font: 9pt sans-serif;