Originally, I had broken out the other site_*.yml files in an attempt to
organize the individual portions of site.yml out, as it was growing long.
But now I have a solution to its length and its consistency that doesn't
involve using multiple playbooks, so I may as well merge everything back
in again.
This playbook *should* assure that we have a file we can use for checking when the last full play was. It being in a playbook at the tail end of site.yml is paramount, since site.yml dying will cause alarms to be set off.