Add support for different FAH Versions

[dmc5179]

While there has not been a release of the FAHClient in quite some time there are still several viable versions for most systems; e.g 7.5 v 7.4. For some systems 7.4 is needed to support different graphics cards or drivers.

Update playbooks/roles to support setting the FAH client/control/viewer versions.

[dmc5179]

This might actually be easier to do once #14 is done

[dmc5179]

There is a newer client, 7.6.1, available for Windows and Debian. The Debian package has also be released as a simple bzip file. The FAHClient application in the 7.6.1 release for Debian does run on other systems like RHEL/CentOS. Look at installing that as well if a packaged version for it doesn't come out soon.

There was also talk from the F@H team of releasing new clients, like a version 8, in the near future.