Updates the use_keyring option for the Keystone Client class
to default to False by default. This provides for a much
easier upgrade path the the most recent keystone-client code
and is backwards compatible with the previous release.
This does not change the default of the no_cache keystone CLI
which will still enable use_keyring by default.
Fixes LP Bug #1087434.
Change-Id: Iaafadde660b0542a9c0a9c1bb742cb369b523a68