hide edit & send buttons when newsletter has already been sent

newsletter/templates/newsletter/newsletter_detail.html

@@ -8,8 +8,12 @@
 
 {% if perms.newsletter.add_newsletter %}
 <p>
+{% if object.expedition_datetime %}
+<span class="big-friendly-button"><strong>Envoyée le {{ object.expedition_datetime }}</strong></span>
+{% else %}
 <a class="big-friendly-button" href="{% url 'newsletter-edit' pk=object.id %}">Modifier</a>
 <a class="big-friendly-button" href="{% url 'newsletter-send' pk=object.id %}">Envoyer</a>
+{% endif %}
 </p>
 {% endif %}