ux: added scroll to two pages

public/app/features/admin/partials/configuration_home.html

 <div class="scroll-canvas">
+  <div gemini-scrollbar>
     <navbar model="ctrl.navModel"></navbar>
     <div class="page-container">
       <div class="page-header">
@@ -31,4 +32,4 @@
         </ol>
       </section>
     </div>
-</div>
+  </div>

public/app/features/plugins/partials/plugin_list.html

-<navbar model="ctrl.navModel"></navbar>
+<div class="scroll-canvas">
+  <div gemini-scrollbar>
 
-<div class="page-container">
+    <navbar model="ctrl.navModel"></navbar>
+
+    <div class="page-container">
       <div class="page-header">
         <h1>
           <i class="icon-gf icon-gf-apps"></i>
@@ -60,5 +63,6 @@
           </li>
         </ol>
       </section>
-
+    </div>
+  </div>
 </div>