Addresses consistency issues that appear with autoincrement fields in
the existing chart, as demonstrated in [1]. It should allow automatic
recovery of 2 out of the 3 (default) cluster members.
It does not address automatic recovery of a complete shutdown of all
cluster nodes.
[1] https://review.openstack.org/#/c/465977/
Change-Id: I84c86e1862f03a6d381bf219b821ea3636049f0b