Fix ec2 credentials commands for new auth
Fix ec2 credentials commands for new auth

These commands were not updated for the new authentication model.

Closes-Bug: 1399757

Change-Id: I5d4beb9d1fa6914fef5e4c7b459cdd967e614b24

openstack/python-openstackclient,BjoernT/python-openstackclient,dtroyer/python-openstackclient,redhat-openstack/python-openstackclient,redhat-openstack/python-openstackclient,openstack/python-openstackclient,BjoernT/python-openstackclient,dtroyer/python-openstackclient