the user guide should talk about os-client-config and clouds.yaml

[Doug Hellmann]

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

The user guide talks about using environment variables and RC files. It should also talk about os-client-config and clouds.yaml, especially for the unified client. See http://docs.openstack.org/developer/os-client-config/ for details.

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Release: 15.0.0 on 2017-05-04 10:31
SHA: 980b7fe8c553955d4bb833de4d9a0c70eb5038b7
Source: https://git.openstack.org/cgit/openstack/openstack-manuals/tree/doc/user-guide/source/common/cli-set-environment-variables-using-openstack-rc.rst
URL: https://docs.openstack.org/user-guide/common/cli-set-environment-variables-using-openstack-rc.html