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/json/ev/simple/ev_1_onos.json b/web/gui/src/main/webapp/json/ev/simple/ev_1_onos.json
index 1776f94..9874ec7 100644
--- a/web/gui/src/main/webapp/json/ev/simple/ev_1_onos.json
+++ b/web/gui/src/main/webapp/json/ev/simple/ev_1_onos.json
@@ -7,7 +7,8 @@
     "labels": [
       "0000ffffffff0008",
       "FF:FF:FF:FF:00:08",
-      "sw-8"
+      "sw-8",
+      ""
     ],
     "metaUi": {
       "x": 400,