Add missing template from previous commit

templates/student_import.html

@@ -0,0 +1,15 @@
+{% extends "admin/base_site.html" %}
+
+{% block breadcrumbs %}
+<div class="breadcrumbs">
+<a href="{% url 'admin:index' %}">Accueil</a>
+&rsaquo; Importation étudiants
+</div>
+{% endblock %}
+
+{% block content %}
+<form action="." method="post" enctype="multipart/form-data">{% csrf_token %}
+  {{ form.as_p }}
+  <input type="submit" value="Envoyer">
+</form>
+{% endblock %}