Resolve "Use Select2 everywhere"

Closes #102 (closed)

TODO: Do not load any stuff from external sources.

biscuit/core/templates/core/edit_group.html

@@ -3,6 +3,12 @@
 {% extends "core/base.html" %}
 {% load bootstrap4 i18n %}
 
+{% block bootstrap4_extra_head %}
+  {{ block.super }}
+  <link href="vendor/select2/dist/css/select2.min.css" rel="stylesheet" />
+  <script src="vendor/select2/dist/js/select2.min.js" />
+{% endblock %}
+
 {% block bootstrap4_title %}{% blocktrans %}Edit group{% endblocktrans %} - {{ block.super }}{% endblock %}
 
 {% block page_title %}{% blocktrans %}Edit group{% endblocktrans %}{% endblock %}