This adds -e to the pre_stop scripts, so that they fail out if
any of their commands fail. This is required, since it's the only
way to communicate whether there is an issue during pre_hook
execution.
"The logs for a Hook handler are not exposed in Pod events.
If a handler fails for some reason, it broadcasts an event."
https://kubernetes.io/docs/concepts/containers/container-lifecycle-hooks/#container-hooks
As an example, this issue was discovered when "touch /tmp/stop"
was failing silently due to a readOnlyRootFilesystem setting,
resulting in pods that would not successfully Terminate until
the grace period was exhausted.
Change-Id: Ic9a228230d944530e31ed61f4239fd434cbb6187
fcaacf94a3