overview: Add a count, info if nothing is changing

The Nodes status detail now shows for how many nodes we have events.
Additionally when there are no events we simply show an alert that
nothing is going on.

puppetboard/templates/index.html

@@ -52,7 +52,8 @@
 
   <div class="row">
     <div class="span12">
-        <h2>Node Status Detail</h2>
+      {% if nodes %}
+        <h2>Nodes status detail ({{nodes|length}})</h2>
         <table class='dashboard table table-striped table-condensed'>
             <thead>
               <tr>
@@ -83,7 +84,12 @@
             {% endfor %}
           </tbody>
         </table>
-
+      {% else %}
+        <h2>Nodes status detail</h2>
+        <div class="alert alert-info">
+          Nothing seems to be changing.
+        </div>
+      {% endif %}
     </div>
   </div>
 </div>