Add a cleanup task to touch a file upon completion of site.yml

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.

playbooks/cleanup.yml

@@ -0,0 +1,12 @@
+#!/usr/bin/env ansible-playbook
+# vim:ft=ansible:
+---
+# Preambulatory system configuration
+- hosts: all
+  tasks:
+    - name: collect service facts
+      service_facts:
+      tags: [ always ]
+    - name: touch ansible timestamp file
+      file: path=/var/lib/ansible-last-run state=touch mode='0644'
+      changed_when: no

site.yml

@@ -34,3 +34,5 @@
   # Housekeeping tags for one-off tasks
 - import_playbook: playbooks/tags_docker-prune.yml
 - import_playbook: playbooks/tags_autoreboot.yml
+  # Last little bit of cleanup
+- import_playbook: playbooks/cleanup.yml