storedObject: add title in form twig and in activity show

src/Bundle/ChillActivityBundle/Resources/views/Activity/show.html.twig

@@ -152,7 +152,7 @@
                     {% if entity.documents|length > 0 %}
                         <ul>
                             {% for d in entity.documents %}
-                                <li>{{ m.download_button(d) }}</li>
+                                <li>{{ d.title }}{{ m.download_button(d) }}</li>
                             {% endfor %}
                         </ul>
                     {% else %}