Update the Drydock chart to be compatible with the latest Helm-Toolkit,
including taking advantage of some HTK manifest generation functionality
and updating the helm_tk.sh script to pull down master
openstack-helm-infra. Also update the default drydock image to point
to the current airshipit master rather than the old attcomdev in quay.
Change-Id: I9a818ae054361749ce16e9a6213fbeed82581f02
Co-Authored-By: Pete Birley <pete@port.direct>
Signed-off-by: Pete Birley <pete@port.direct>