add unread count to thread title in topic view

app/templates/topics/topic.html

@@ -49,7 +49,13 @@
 {%- for thread in threads -%}
 <div class="topic-info plank">
   <div class="title-container">
-    <span class="info thread-title-counter"><a href="{{url_for('threads.thread_by_id', thread_id=thread.id)}}">{{thread.title}}</a>
+    <span class="info thread-title-counter">
+      <ul class="horizontal">
+        <li><a href="{{url_for('threads.thread_by_id', thread_id=thread.id)}}">{{thread.title}}</a></li>
+        {%- if subscriptions[thread.id] -%}
+        <li>({{subscriptions[thread.id]}} unread)</li>
+        {%- endif -%}
+      </ul>
     </span>
     <ul class="horizontal">
     {%- if thread.is_locked -%}