[PYTHON] Upgrade Sphinx

The locally installed Sphinx was old, so I updated it.

procedure

Check the version before installation

% pip show sphinx                                                             
---
Name: Sphinx
Version: 1.2.3
Location: /Library/Python/2.7/site-packages/Sphinx-1.2.3-py2.7.egg
Requires: Pygments, docutils, Jinja2

update

% sudo pip install sphinx --upgrade --ignore-installed six

Check the version after the update

% pip show sphinx
---
Name: Sphinx
Version: 1.4.6
Location: /Library/Python/2.7/site-packages
Requires: babel, Jinja2, alabaster, imagesize, six, Pygments, snowballstemmer, docutils