Add an extras_require option to setup.py (more)

Just like how you can do:
pip install ipython[notebook]

You can now do:
pip install plotly[PY2.6]

Author: theengineear

setup.py

@@ -41,9 +41,6 @@ def readme():
                 'plotly/matplotlylib/mplexporter',
                 'plotly/matplotlylib/mplexporter/renderers'],
       package_data={'plotly': ['graph_reference/*.json', 'widgets/*.js']},
-      install_requires=['requests',
-                        'six',
-                        'pytz',
-                        'ordereddict',
-                        'simplejson'],
+      install_requires=['requests', 'six', 'pytz'],
+      extras_require={"PY2.6": ['simplejson', 'ordereddict']},
       zip_safe=False)