Use keystone.host in stackrc
Use keystone.host in stackrc

/root/stackrc has a hardcoded value of localhost for OS_AUTH_URL,
which doesn't help when we can't talk to it due to VIP changes. Set
it to keystone.host.

Change-Id: If952f383e8970e3298c36cdd750f6c6a20209e81

openstack/tripleo-image-elements,rdo-management/tripleo-image-elements,radez/tripleo-image-elements,openstack/tripleo-image-elements,radez/tripleo-image-elements,rdo-management/tripleo-image-elements