Updated openstack/openstack
Project: openstack-infra/devstack-gate  f32312589588be86b9f7e169d986449561d05023

don't use screen for grenade

now that the process stop pieces of devstack work much better,
it's not clear that we need to actually use screen to stuff in
the service starts / stops.

We should try to do this without screen.

Change-Id: Icc5b9b5f8dcde22f2864d3ba6aa91d0afe936d7a