Remove fixed width/height columns now that images are resized

_includes/person-card.html

 </p>
-<div class="col-sm-4 card text-xs-center" style="width: 250px; height: 270px">
+<div class="col-sm-4 card text-xs-center">
   </br>
   <a href="{{ person.url }}">
     <img class="img-circle" style="width: 75%" src="{{ person.image | prepend: site.baseurl }}" alt="Photo of {{ person.firstname }} {{ person.lastname }}" />