Filetreediff: expose it for users that have it enabled (#564)

We don't expose it to all the users yet, but we want to expose it for
those that we already enabled it on the Django Admin.

Author: humitos

readthedocsext/theme/templates/projects/addons_form.html

@@ -48,6 +48,7 @@
         <a class="item" data-tab="notifications">{% trans "Notifications" %}</a>
         <a class="item" data-tab="analytics">{% trans "Analytics" %}</a>
         <a class="item" data-tab="docdiff">{% trans "Visual diff" %}</a>
+        <a class="item" data-tab="filetreediff">{% trans "File tree diff" %}</a>
         <a class="item" data-tab="link-previews">{% trans "Link previews" %}</a>
         <a class="item" data-tab="hotkeys">{% trans "Hotkeys" %}</a>
         <a class="item" data-tab="advanced">{% trans "Advanced" %}</a>
@@ -98,6 +99,13 @@
         </div>
       {% endblock addons_docdiff %}
 
+      {% block addons_filetreediff %}
+        <div class="ui tab" data-tab="filetreediff">
+          {{ form.filetreediff_enabled | as_crispy_field }}
+          {{ form.filetreediff_ignored_files | as_crispy_field }}
+        </div>
+      {% endblock addons_filetreediff %}
+
       {% block addons_link_previews %}
         <div class="ui tab" data-tab="link-previews">
           {{ form.linkpreviews_enabled | as_crispy_field }}