fold people

_includes/alumni.html

-<div class="people">
-{% for person in include.people %}
+<div class="people panel">
+
+  {% assign grouped_people = include.people | group_by: 'position' | sort: 'name' %}
+  {% for group in grouped_people %}
+  {% assign position = group.name %}
+  {% assign id = group.name | replace:' ','-' %}
+  <div class="panel-heading">
+    <h6 class="panel-title">
+      <a data-toggle="collapse" href="#{{id}}" style="color:black">{{position}} ↯</a>
+    </h6>
+  </div>
+
+  <div id="{{id}}" class="panel-collapse collapse">
+    {% for person in group.items %}
     <div class="row">
       <div class="col-sm-1" >
         <a href="{{ person.url }}" >{% include person-photo-small.html %}</a>
@@ -11,3 +23,5 @@
     </div>
     {% endfor %}
   </div>
+  {% endfor %}
+</div>