Option auth_uri from group keystone_authtoken is deprecated [1].
Use option www_authenticate_uri from group keystone_authtoken.
Does not change auth_uri for providers because [2] will change
that to auth_url.
[1] https://review.openstack.org/#/c/508522/
[2] https://review.openstack.org/#/c/588504/
Change-Id: I134f6318f3d409f9aa3368e93e9ef55a82ab6788