fix ruamel.yaml on 0.14.X for now

[AvdN]

Thank you for using ruamel.yaml.

There will be API changes in the 0.15+ versions, that might lead to warnings that
your users could see.
Therefore please release a version of your package with this change, so that it will not
automatically take the latest ruamel.yaml release.

[sdodson]

@kwoodson FYI, something for us to be aware of in openshift-ansible.

[kwoodson]

@sdodson, thanks

[AvdN]

I looked at the actual usage or ruamel.yaml in openshift-restclient just now and it seems easy to add a few lines that will make it possible to use either the old or the new API depending on which ruamel.yaml is installed. That should make it easier if you have multiple packages that are dependent on ruamel.yaml and that are installed together.
http://yaml.readthedocs.io/en/latest/api.html#transparent-usage-of-new-and-old-api