refactor(itim): Add Cluster type to index page

ref: #244 #71

app/itim/templates/itim/cluster_index.html.j2

@@ -6,7 +6,7 @@
 <table class="data">
     <tr>
         <th>Title</th>
-        <th>Cluster / Device</th>
+        <th>Type</th>
         <th>Organization</th>
         <th>&nbsp;</th>
     </tr>
@@ -15,10 +15,10 @@
     <tr>
         <td><a href="{% url 'ITIM:_cluster_view' pk=item.id %}">{{ item.name }}</a></td>
         <td>
-        {% if item.device %}
-          {{ item.device }}
+        {% if item.cluster_type %}
+          {{ item.cluster_type }}
         {% else %}
-          {{ item.cluster }}
+          &nbsp;
         {% endif %}
         </td>
         <td>{{ item.organization }}</td>