GUI -- store ref to node/link selection in backing data.
- tweaking force-layout parameters; now host-to-host intent path is highlighted.
- injectTestEvent() now uses recursion to look for appropriate json files.
- implemented updateHost() event.
- some refactoring cleanup in topo2.js

Change-Id: I888f05032d3c9df6470bd4d2f399f61efb9dbd46
diff --git a/web/gui/src/main/webapp/topo2.css b/web/gui/src/main/webapp/topo2.css
index a5bf661..acd0bc9 100644
--- a/web/gui/src/main/webapp/topo2.css
+++ b/web/gui/src/main/webapp/topo2.css
@@ -53,13 +53,18 @@
     fill: #846;
 }
 
-#topo svg .node text {
-    stroke: none;
+#topo svg .node.device text {
     fill: white;
     font: 10pt sans-serif;
     pointer-events: none;
 }
 
+#topo svg .node.host text {
+    fill: #846;
+    font: 9pt sans-serif;
+    pointer-events: none;
+}
+
 #topo svg .node.selected rect,
 #topo svg .node.selected circle {
     filter: url(#blue-glow);
@@ -73,7 +78,7 @@
 
 #topo svg .link.showPath {
     stroke: #f00;
-    stroke-width: 4px;
+    stroke-width: 6px;
 }
 
 /* for debugging */