Index in contributor-guide

[Acidburn0zzz]

This bug tracker is for errors with the documentation, use the following as a template and remove or add fields as you see fit. Convert [ ] into [x] to check boxes:

- [ ] This doc is inaccurate in this way: ______
- [ ] This is a doc addition request.
- [ ] I have a fix to the document that I can paste below including example: input and output.

If you have a troubleshooting or support issue, use the following resources:

 - Ask OpenStack: http://ask.openstack.org
 - The mailing list: http://lists.openstack.org
 - IRC: 'openstack' channel on Freenode

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Release: 0.0.1.dev17 on 2017-12-11 20:57
SHA: 04ff3a3996139e889a24588663b5886aa1553f98
Source: https://git.openstack.org/cgit/openstack/contributor-guide/tree/doc/source/genindex.rst
URL: https://docs.openstack.org/contributors/genindex.html

[Frank Kloeker (f-kloeker)]

seems duplicated to #1738573