backport: pike

Closes-Bug: #1729564
Change-Id: If6db5fad1f23e0afaadcad97b4f37a13e34de9fa
(cherry picked from commit 994c80c7)

Useful api_interface_address variable has been define here:
https://github.com/openstack/kolla-ansible/blob/master/ansible/group_vars/all.yml#L57
In order to simplify codebase we must use it as much as possible.

Change-Id: I18fec19bf69e05a22a4142a9cd1165eccd022455

wait_for module waits 300 seconds for the port started or stopped.  This
is meaningless and useless in precheck. This patch change timeout to 1
seconds.

Change-Id: I9b251ec4ba17ce446655917e8ef5e152ef947298
Closes-Bug: #1688152

To avoid many merge conflicts and re-works
* Panko
* Octavia
* Ceph
* MariaDB

Co-Authored-By: caoyuan <cao.yuan@99cloud.net>
Partially-implements: blueprint condition-pre-check
Change-Id: I3d2766d0d9f01ad4052731c7219a2d0635527ac5

* Merge prechecks.yml and site.yml playbook
* Create empty precheck.yml into all roles.

Change-Id: I8a138558a26c0a2a66c5fd48ed37be657c99c1dd
Implements: blueprint condition-pre-check

TrivialFix

Change-Id: Ib31ef8e1067e4249bb39959aefb5d3de51fad89c

- This change indroduces a merge_yaml action_plugin
- This change generates bifrost yaml configs.

Change-Id: I9814e6a5d55cbd46c4b60c06ed70ed54a575bd2f
Implements: blueprint bifrost-support

This partially implements iscsi and lvm2 support for cinder
in Kolla. Adds ansible code for iscsid and tgtd containers.

Change-Id: I2a4cfcf104397396ea61a09637d9ef3fc77b515f
Partially-Implements: blueprint iscsi-lvm2-docker

DocImpact

Partially-implements: bp kolla-reconfig
Change-Id: I9738e80960bcfbef18d1ef1b7942f81c45684e85

After introduction of pull action and turing every main.yml into
{{action}}.yml we lost ability to perform upgrade

Change-Id: Ie9fa2cd083b061033abc733fba53d54f9c55e393
Fixes-Bug: #1538210