logo link to current tree level

rather than top level

IPython/html/templates/page.html

@@ -49,7 +49,7 b''
 <div id="header" class="navbar navbar-static-top">
   <div class="navbar-inner navbar-nobg">
     <div class="container">
-    <div id="ipython_notebook" class="nav brand pull-left"><a href="{{base_project_url}}" alt='dashboard'><img src='{{static_url("base/images/ipynblogo.png") }}' alt='IPython Notebook'/></a></div>
+    <div id="ipython_notebook" class="nav brand pull-left"><a href="{{base_project_url}}tree/{{notebook_path}}" alt='dashboard'><img src='{{static_url("base/images/ipynblogo.png") }}' alt='IPython Notebook'/></a></div>
 
     {% block login_widget %}