Add daily/weekly systemd timer setup

roles/arch/templates/timer/weekly_timer.j2

@@ -0,0 +1,12 @@
+# {{ ansible_managed }} {{ ansible_date_time.time }} {{ ansible_date_time.date }}
+#
+[Unit]
+Description=Timer which runs all services on a weekly basis inside the weekly.target.wants directory
+
+[Timer]
+OnCalendar=weekly
+Unit=weekly.target
+Persistent=true
+
+[Install]
+WantedBy=timers.target