[Bugfix] Fix user follow

* The link didn’t have a closing tag
* The whole mechanism didn’t work

I probably submitted a previous patch…

calsocial/templates/profile-details.html

@@ -6,7 +6,7 @@
     <small>@{{ profile.user.username}}</small>
 </h1>
     {% if profile.user != current_user %}
-<a href="{{ url_for('follow_user', username=profile.user.username) }}">{% trans %}Follow{% endtrans %}
+<a href="{{ url_for('follow_user', username=profile.user.username) }}">{% trans %}Follow{% endtrans %}</a>
     {% endif %}
 
 <h2>