This PS updates the mariadb chart to both support adoption of a
single instance of mariadb running the bash driven chart, which
did not support reforming a galera cluster by tracking state using
a configmap. Additionally basic logic is added for upgrading the
database as part of the normal rolling update flow.
Change-Id: I412de507112b38d6d2534e89f2a02f84bef3da63
Signed-off-by: Pete Birley <pete@port.direct>