Add node autoready oneshot unit

This replicates some of the more important functionality of the defunct
pvc-flush.service unit. On presence of a trigger file (i.e.
/etc/pvc/autoready), it will trigger a "node ready" on boot. It does
nothing on shutdown as this must be handled by other mechanisms, though
a similar autoflush could be added as well.

node-daemon/pvcautoready.service

@@ -0,0 +1,19 @@
+# Parallel Virtual Cluster autoready oneshot
+
+[Unit]
+Description = Parallel Virtual Cluster autoready oneshot
+After = pvcnoded.service pvcapid.service zookeeper.service libvirtd.service ssh.service ceph.target network-online.target
+Wants = pvcnoded.service pvcapid.service
+PartOf = pvc.target
+ConditionPathExists=/etc/pvc/autoready
+
+[Service]
+Type = oneshot
+RemainAfterExit = false
+WorkingDirectory = /usr/share/pvc
+TimeoutSec = 31min
+ExecStartPre = /bin/sleep 60
+ExecStart = /usr/bin/pvc -c local node ready --wait
+
+[Install]
+WantedBy = pvc.target