Add link to new ui and feedback button

appengine/swarming/templates/user_tasks.html

 {% extends "swarming/base.html" %}
 
 
 {% block headers %}
 <style>
   h1 {
     margin-top: 10px;
     margin-bottom: 10px;
   }
 
@@ skipping 106 matching lines @@
   }
 </script>
 {% endblock %}
 
 
 {% block body %}
 {% import 'swarming/bot_view.html' as bot_view %}
 
 <h1>Tasks</h1>
 <a href="/">Back to root</a>
+<br/>
+<a href="/newui/tasklist">Try out the new task list</a>
 <p>
 <form id="filter" name="filter" method="GET">
 <input type="range" id="limitRange" name="limit" value="{{limit}}" min=10
     max=500 step=5 onchange="update_limit_text(this.value);"
     onmousemove="update_limit_text(this.value);" >
 <input type="text" id="limitText" value="{{limit}}" maxlength="3"
     onchange="update_limit_range(this.value);">
 <input type="submit" value="Set limit">
 <p>
 <table class=layout_table title="Select order and filter">
@@ skipping 226 matching lines @@
       </tfoot>
     {% else %}
       {{ next_page_link() }}
     {% endif %}
   </table>
 {% else %}
   No data to show for this selection.
 {% endif %}
 
 {% endblock %}