Developers that need to stack and re-stack non-AIO compute-only
environments will want to be able to keep the compute node uuid the
same across runs. This mimics the behavior of a deployment tool that
pre-creates the uuids, so it matches pretty well. Default to the
current behavior of create-on-start, but allow forcing it ahead of
time to something specific.
Change-Id: Icab0b783e2233cad9a93c04758a5bccac0832203
72cf4e6006