Improve template for autoscaling stack

as a debugging helper, add a stack output that will render
a CLI command that will make approx the same API call the alarms
created by the stack would use.

Also, fix some quotation so the file is closer to actual JSON format
(it is still not 100% JSON though, as it uses some gabbi-specific
substitutions).

Related-Issue: PRODX-46006
Change-Id: Icd8e2ab19af4df9bef4c018fc6e4d06c6234e9fc
1 file changed