Show availability in links panel

bookwyrm/templates/book/file_links/links.html

@@ -30,6 +30,12 @@
     <li>
         <a href="{{ link.url }}" rel="noopener" target="_blank" title="{{ link.url }}" data-modal-open="{{ verify_modal }}">{{ link.name }}</a>
         ({{ link.filetype }})
+
+        {% if link.availability != "free" %}
+        <p class="help">
+            {{ link.get_availability_display }}
+        </p>
+        {% endif %}
     </li>
     {% endfor %}
 </ul>