use Jupyter logo in the notebook header

and favicon

IPython/core/tests/test_display.py

@@ -52,9 +52,9 b' def test_image_filename_defaults():'
     nt.assert_raises(ValueError, display.Image, data='this is not an image', format='badformat', embed=True)
     from IPython.html import DEFAULT_STATIC_FILES_PATH
     # check boths paths to allow packages to test at build and install time
-    imgfile = os.path.join(tpath, 'html/static/base/images/ipynblogo.png')
+    imgfile = os.path.join(tpath, 'html/static/base/images/logo.png')
     if not os.path.exists(imgfile):
-        imgfile = os.path.join(DEFAULT_STATIC_FILES_PATH, 'base/images/ipynblogo.png')
+        imgfile = os.path.join(DEFAULT_STATIC_FILES_PATH, 'base/images/logo.png')
     img = display.Image(filename=imgfile)
     nt.assert_equal('png', img.format)
     nt.assert_is_not_none(img._repr_png_())

IPython/html/templates/page.html

@@ -72,7 +72,7 b''
 
 <div id="header" class="navbar navbar-static-top">
   <div class="container">
-  <div id="ipython_notebook" class="nav navbar-brand pull-left"><a href="{{base_url}}tree" alt='dashboard'>{% block logo %}<img src='{{static_url("base/images/ipynblogo.png") }}' alt='IPython Notebook'/>{% endblock %}</a></div>
+  <div id="ipython_notebook" class="nav navbar-brand pull-left"><a href="{{base_url}}tree" alt='dashboard'>{% block logo %}<img src='{{static_url("base/images/logo.png") }}' alt='Jupyter Notebook'/>{% endblock %}</a></div>
 
   {% block login_widget %}