Moves common RestfulTestCase to it's own module.

This is in preparation for larger refactorings to make the test suite
faster and easier to understand.

Change-Id: I86d5be0324cca744b3109989815ef1dc720d1f8c
Change deprecated CLI arguments

According to keystoneclient/shell.py, --token and --endpoint (with
their accompanying ENV vars SERVICE_TOKEN and SERVICE_ENDPOINT)
were retained only for Essex compatibility and should have been
removed during Grizzly, replaced with --os-token (OS_SERVICE_TOKEN)
and  --os-endpoint (OS_SERVICE_ENDPOINT).

This patch updates a couple of doc references to the old options,
and the sample_data tool.

Change-Id: I87060764f40b1612e3a440c3406d094536af4c9c
Merge "Moves common RestfulTestCase to it's own module."
Merge "Change deprecated CLI arguments"