Pass arguments to v3 keystoneclient by kwarg

Keystoneclient has added the positional decorator which emits a warning
if arguments aren't passed by keyword. This means we are getting
warnings in certain places in openstackclient.

Change-Id: Ic5446cd6f122cbb56fce543011386d53bc31fe18
Closes-Bug: #1302199
Merge "Pass arguments to v3 keystoneclient by kwarg"