Rename [wheel] section to [bdist_wheel] as the former is legacy

For additional details, see:

https://bitbucket.org/pypa/wheel/src/54ddbcc9cec25e1f4d111a142b8bfaa163130a61/wheel/bdist_wheel.py?fileviewer=file-view-default#bdist_wheel.py-119:125

http://pythonwheels.com/

setup.cfg

@@ -20,7 +20,7 @@ output_dir = sphinx/locale/
 domain = sphinx
 directory = sphinx/locale/
 
-[wheel]
+[bdist_wheel]
 universal = 1
 
 [flake8]