Upgrade to Django 1.11

- Deprecation warnings using Django 1.8 are resolved.
- Deprecation warnings using Django 1.11 are resolved.

- Admin: grappelli is no longer used.
- Upgrade to django-autocomplete-light v3 (v2 is not 1.11 compatible).
  * autocomplete.modelform_factory being dropped, code uses dal Select2
    views and widgets.

gestioncof/templates/registration/password_change_done.html

@@ -5,5 +5,5 @@
 
 {% block realcontent %}
                 <h2>Mot de passe modifié avec succès !</h2>
-		        <h3><a href="{% url "gestioncof.views.home" %}">Retour au menu principal</a></h3>
+		        <h3><a href="{% url "home" %}">Retour au menu principal</a></h3>
 {% endblock %}

gestioncof/templates/registration/password_change_form.html

@@ -5,7 +5,7 @@
 
 {% block realcontent %}
                 <h2>Changement de mot de passe</h2>
-                <form class="form-horizontal" method="post" action="{% url 'django.contrib.auth.views.password_change' %}">
+                <form class="form-horizontal" method="post" action="{% url 'password_change' %}">
                 {% csrf_token %}
                 {{ form | bootstrap }}
                 <input type="submit" class="btn btn-primary pull-right" value="Changer" />