Show new admin banner to admins only

modoboa/core/templates/core/dashboard.html

@@ -5,10 +5,12 @@
 {% block pagetitle %}{% trans "Dashboard" %}{% endblock %}
 
 {% block container_content %}
+  {% if user.is_admin %}
   <div class="alert alert-warning text-center">
     <strong>Want to check the new admin interface?</strong>
     <a class="btn btn-default" style="margin-left: 20px;" href="/new-admin" target="_blank">Go to Modoboa v2</a>
   </div>
+  {% endif %}
 
   <div class="row">
     <div class="col-xs-12 col-sm-offset-1 col-sm-10">