undercloud-container: deployment isn't idempotent because of passwords

[Emilien Macchi]

On undercloud-container, we don't run an Heat stack, and we generate tripleo heat templates environments at every install command.

It means that all resources of OS::TripleO::RandomString type will be re-generated, while we don't want that since we want our deployment to be idempotent. (Note: on classic deployment these resources aren't executed after an install).

So we need to move these resources into tripleo-common/constants so the passwords/secrets will be generated once, stored and re-used every time we try to re-install or/and update.

[OpenStack Infra (hudson-openstack)]

Related fix proposed to branch: master
Review: https://review.openstack.org/526151

[OpenStack Infra (hudson-openstack)]

Related fix proposed to branch: master
Review: https://review.openstack.org/526155

[OpenStack Infra (hudson-openstack)]

Change abandoned by Emilien Macchi (<email address hidden>) on branch: master
Review: https://review.openstack.org/526155

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/526151
Committed: https://git.openstack.org/cgit/openstack/tripleo-common/commit/?id=5dc478db69014bb6ebaa203d865d51853edc4ded
Submitter: Zuul
Branch: master

commit 5dc478db69014bb6ebaa203d865d51853edc4ded
Author: Dan Prince <email address hidden>
Date: Thu Dec 21 13:41:22 2017 -0500

    Manage legacy OS::TripleO::RandomString resources in constants

    Instead of generated OS::TripleO::RandomString from the Heat Template,
    make the password generated among other passwords so we can re-use the
    data across undercloud-container re-install or updates, when Heat and
    environments are re-generated.

    Note: it keeps the same password constraints as it was in THT.

    Co-Authored-By: Dan Prince <email address hidden>
    Co-Authored-By: Martin André <email address hidden>
    Change-Id: I9da2220ce5635d06c2ca9a21bd07eb2b6ee50aaa
    Related-Bug: #1736779