Changelog:
a15448e tests: add new scenario subset_update
3dd96da rolling_update: fix pre and post osd upgrade play
dc1a4c2 update: support upgrading a subset of nodes
c5a8343 tests: ensure ca-certificates is up to date
a890d6a tests: remove all references to ceph_stable_release
7495de3 ceph-defaults: set ceph_stable_release default to the stable branch release
a8026b3 tests: set rgw_instances in collect-logs.yml
dda2368 tests: update collect-logs.yml playbook
6dd85f3 tests: move collect-logs.yml to ceph-ansible repo
0a93de9 purge: add remove_docker tag
0ede37b purge: add container_binary needed for zap osds
ce80ed9 ceph-defaults: set quay.io as the default registry
e7b0af3 ceph-container-engine: allow override container_package_name and container_service_name