Add Host OS test case for cpupower modification of governor settings

[rquander]

Add an automated test to the Host OS Test Suite to test cpupower modification of governor settings.

[rquander]

Test case enhancement is still in progress.

[rquander]

@PavithraDP submitted a new PR for this test in the avocado-misc-tests repository (#228). Once all review comments have been resolved and the PR is merged, I'll close this Issue.

[rquander]

The new test in avocado-misc-tests PR #228 is merged. I need to add this test to the Host test sanity.cfg file and then close this Issue.

[rquander]

Resolved with Pull Request #50