GUI -- TopoView - Implemented much of the node selection logic. (WIP)
- introduced topoSelect.js.

Change-Id: Ic843c7d8dc2249fe0cb8c33de60dce12c07aea44
diff --git a/web/gui/src/main/webapp/app/fw/layer/panel.js b/web/gui/src/main/webapp/app/fw/layer/panel.js
index a29c175..46934f1 100644
--- a/web/gui/src/main/webapp/app/fw/layer/panel.js
+++ b/web/gui/src/main/webapp/app/fw/layer/panel.js
@@ -77,6 +77,7 @@
                 width: panelWidth,
                 height: panelHeight,
                 isVisible: panelIsVisible,
+                classed: classed,
                 el: panelEl
             };
 
@@ -146,6 +147,10 @@
             return p.on;
         }
 
+        function classed(cls, bool) {
+            return p.el.classed(cls, bool);
+        }
+
         function panelEl() {
             return p.el;
         }
diff --git a/web/gui/src/main/webapp/app/fw/svg/svgUtil.js b/web/gui/src/main/webapp/app/fw/svg/svgUtil.js
index ab56ddd..2c47d44 100644
--- a/web/gui/src/main/webapp/app/fw/svg/svgUtil.js
+++ b/web/gui/src/main/webapp/app/fw/svg/svgUtil.js
@@ -34,6 +34,7 @@
             $log = _$log_;
             fs = _fs_;
 
+            // TODO: change 'force' ref to be 'force.alpha' ref.
             function createDragBehavior(force, selectCb, atDragEnd,
                                         dragEnabled, clickEnabled) {
                 var draggedThreshold = d3.scale.linear()