Closes-Bug:#1455163,Closes-Bug:#1456152

1) Added ‘Move’ cursor for pannable area, ‘Grab/grabbing’ cursor for nodes, ‘default’ cursor to identify which area in the view portion is pannable - For bug 1455163

2) Increased svg area to 2000x2000 pixels by default to accomodate the unpredictable length of links. Also increasing further more in case the canvas size is more than 2000px (may happen when there are more than 20 VMs, for example)

Change-Id: I1972bfd47d13bb0d5d21e6ae2a773c3c69c98a86

webroot/css/contrail.custom.css

@@ -1737,11 +1737,31 @@ color: #b94a48;
 .font-element i.icon-contrail-virtual-machine, .font-element i.icon-contrail-virtual-machine-left, .font-element i.icon-contrail-virtual-machine-right {
     font-size: 20px;
 }
+/*Style for the underlay topology svg elements*/
 .topology-visualization svg {
+    cursor:move;
     height: auto !important;
     width: auto !important;
+}
+
+.topology-visualization svg g.element {
+    cursor:default;
+    cursor:grab;
+    cursor:-webkit-grab;
+    cursor:-moz-grab;
+}
 
+.topology-visualization svg g.element:active {
+    cursor:default;
+    cursor:grabbing;
+    cursor:-webkit-grabbing;
+    cursor:-moz-grabbing;
 }
+
+.topology-visualization .connection-wrap{
+    cursor:default;
+}
+
 .topology-visualization svg text {
     font-size: 10px;
     font-weight:200;