Bug Fixes

- keystoneclient.client.Client() does not work properly at least with Rackspace Identity; it also appears keystoneclient itself doesn't use it for keystoneclient.shell. Rather everything seems to hardcode a Keystone version, in this case keystoneclient.v2_0.client.Client. So we'll do likewise for now until the discovery stuff is fixed.
--- Updated usage of keystoneclient.client to keystoneclient.v2_0.client
--- Updated mocks to mock out the keystoneclient.v2_0.client
--- left existing mocks in place so it is easy to revert, and documented the changes and why
--- keystoneclient.v2_0.client.Client can throw an exception on creation; as a result get_client needed to be try/excepted and a new test added
- bugfix: discovered a bug in the deuceclient.shell that failed to capture the correct username
- bugfix: apikey is not supported via keystoneclient at this time; though we could probably monkey patch it to do so
- bugfix: some parameters were in the incorrect order
--- updated to be in a uniform order
- bugfix: AuthToken is no longer a property b/c properties don't work well with abstract base classes
Converted AuthToken() back to property AuthToken

- Properties do not play well with Abstract Base Classes so AuthToken as a property cannot be derived
--- Changed the abstractmethod from AuthToken to _AuthToken
--- Updated base class's AuthToken to call _AuthToken which by default is not implemented
--- Converted AuthToken back to property and updated all references accordingly