The major upgrade procedure has been collecting new bits over time,
but has not really had bits cleaned out of it when unnecessary. Some
parts have also never been used.
This patch does the following:
1. Consolidates the basic deploy node changes into a single playbook
which is tagged, and therefore easy to run stand alone and use
with skip-tags if necessary.
2. Removes the ceph-galaxy-removal playbook which was for the P->Q
upgrade only.
3. Removes the ansible_fact_cleanup playbook and script - the first
ran the second which was a bit pointless, given it could be done
in a playbook task instead. This has been rolled into the
deploy-config-changes playbook.
4. Removes the memcached-flush playbook which was only actually
required for the N->O upgrade. The functionality to enable the
flush more surgically was enabled via a var in the keystone role
in [a], so that can be used in the future if need be.
5. Consolidates user-secrets-adjustment into the
deploy-config-changes playbook, and also removes the var renames
which were only appropriate for the Q->R upgrade.
6. Removes the make_rst_table, migrate_openstack_vars and
test_migrate_openstack_vars scripts which do not ever appear to
have been used.
7. Changes the limited playbook run for galera_all/rabbitmq_all from
only doing lxc-containers-create.yml to all of setup_hosts to
ensure that any hosts missed out in the previous step is handled
in that step. This is useful if rabbitmq/galera are installed on
hosts instead of in containers.
8. Removed the extra backup of the /etc/openstack_deploy directory
given that it is already archived by the run-upgrade script.
9. Made the backup of the OSA configuration done in run-upgrade
idempotent.
10. Removes the reference content for upgrades, given that most of
it is duplicated and the simplified structure negates the need
for a reference guide.
11. Change the infrastructure part of the upgrade to be simpler,
and use the setup-infrastructure playbook.
[a] https://review.openstack.org/#/q/topic:bug/1793389
Related-Bug: #1808041
Change-Id: I58732dc181ee985364e97aa890987a98544ed06c
3fb15ad780