Currently, the idiomatic "download image and retag to pcmklatest"
happens at step 2 during upgrade. This doesn't work if the stack
is already containerized before the upgrade, because pacemaker
is still running at step 2.
Reshuffle the steps at which the various upgrade tasks are run,
while keeping the ordering guarantees of the upgrade flow:
. Deletion of non-containerized resources happens at step 1,
to allow calling pcs while pacemaker is running.
. Pacemaker is stopped at step 2.
. Docker images for containerized resources are upgraded at
step 3, after the cluster is guaranteed to be stopped.
. Pacemaker is restarted at step 4 as before, once we know
that all resources have been upgraded, yum packages updated
and any potential docker restart has been executed.
Also change the way we detect containerized resources, so that
the predicate still remains valid past step 2 when pacemaker
has been stopped and has deleted its containerized resources.
Change-Id: I85e11dd93c7fd2c42e71b467f46b0044d4516524
f37c06cd9d