Add the post new topic button to group searches

tildes/tildes/templates/search.jinja2

@@ -35,8 +35,14 @@
 
   <p><a href="/">Back to home page</a></p>
 
-  {% if request.user and request.user.subscriptions %}
+  {% if request.user %}
     <div class="divider"></div>
+
+    {% if request.has_permission('post_topic', group) %}
+      <a href="/~{{ group.path }}/new_topic" class="btn btn-primary">Post a new topic</a>
+    {% endif %}
+
+    {% if request.user.subscriptions %}
       <ul class="nav">
         <li>Subscriptions</li>
         <ul class="nav">
@@ -46,5 +52,6 @@
         </ul>
       </ul>
     {% endif %}
+  {% endif %}
 
 {% endblock %}