add systemd timer for backups

templates/status-email-root.j2

@@ -0,0 +1,4 @@
+#!/bin/bash
+set -euo pipefail
+
+systemctl status "$1" | mail -s "service $1 failed on $( hostname )" root || true

templates/status-email-root@.service.j2

@@ -0,0 +1,7 @@
+[Unit]
+Description=Send a mail to root in case of a service failure
+
+[Service]
+Type=oneshot
+ExecStart=/usr/local/bin/status-email-root %i
+

templates/timer.j2

@@ -0,0 +1,11 @@
+[Unit]
+Description=Execute backup job
+
+[Timer]
+Persistent=true
+{% if "OnCalendar" in backups.jobs[item] %}
+OnCalendar={{ backups.jobs[item].OnCalendar }}
+{% endif %}
+
+[Install]
+WantedBy=timers.target