change jupyter logo name

docs/source/_templates/breadcrumbs.html

@@ -3,7 +3,7 @@
 {% block breadcrumbs %}
   <div>
     <a href="http://www.jupyter.org/documentation">
-      <img src="./_static/jl.svg" width="120px">
+      <img src="./_static/jupyter_logo.svg" width="120px">
     </a>
   </div>
   <li><a href="{{ pathto(master_doc) }}">{{ _('Docs') }}</a> &raquo;</li>