this patch pulls the ansible deploy interface code
and related ansible playbooks and auxiliary files
from ironic-staging-drivers project into main ironic tree.
As discussed in the spec, the use of ramdisk callbacks
(lookup and hearbeats) is now mandatory with this deploy interface.
Playbooks and modules were updated to require Ansible>=2.4,
and custom Ansible module for executing 'parted' was replaced
with usage of built-in Ansible module.
The custom Ansible callback plugin now uses journald logger
by default to adapt to the default DevStack setup.
Documentation and devstack plugin changes enabling automated
testing of this interface will be proposed in followup patches.
Change-Id: I43f54688287953ccb1c2836437aea76236e6560b
Related-Bug: #1526308
9b1a7ceb4b