Fix Keystone Auth File

Due to the following commit, the admin_token should not be set
in the openstack auth file:

https://github.com/stackforge/puppet-openstack/commit/8b37baa3661fd2a3d4bc9d67b21a373f58cd1af9

Otherwise, token-based auth is used and OS tenant, password,
username, etc. vaariables must be used at the CLI for each command.