GUI -- Tabular views have divs that encapsulate the header to make math easier for calculating table height. - fixed bug in Device Details Panel where Ports table wouldn't scroll. - Minor refactoring

Change-Id: I2d8133fb4a92f82087566084143c32deb7393fb3
diff --git a/web/gui/src/main/webapp/app/view/app/app.html b/web/gui/src/main/webapp/app/view/app/app.html
index 45f9cbc..ced8ec2 100644
--- a/web/gui/src/main/webapp/app/view/app/app.html
+++ b/web/gui/src/main/webapp/app/view/app/app.html
@@ -1,6 +1,6 @@
 <!-- app partial HTML -->
 <div id="ov-app">
-    <div>
+    <div class="tabular-header">
         <h2>Applications ({{ctrl.tableData.length}} total)</h2>
         <div class="ctrl-btns">
             <div icon icon-size="36" icon-id="plus"></div>
@@ -9,6 +9,7 @@
             <div icon icon-size="36" icon-id="stop" class="disabled"></div>
         </div>
     </div>
+
     <table class="summary-list"
            onos-fixed-header
            onos-sortable-header
@@ -44,5 +45,4 @@
             </tr>
         </tbody>
     </table>
-
 </div>