Pointed intersphinx links to Python's default version.

# Links to Python's docs should reference the most recent version of the 2.x

# branch, which is located at this URL.

intersphinx_mapping = {

    'python': ('http://docs.python.org/2.7', None),

    'python': ('http://docs.python.org/', None),

    'sphinx': ('http://sphinx-doc.org/', None),

    'six': ('http://pythonhosted.org/six/', None),

    'simplejson': ('http://simplejson.readthedocs.org/en/latest/', None),