Comment 14 for bug 1609056

Reviewed: https://review.openstack.org/350605
Committed: https://git.openstack.org/cgit/openstack/openstack-ansible/commit/?id=4c620fee1f509d15009fdc18c3ad53cac7bd5f69
Submitter: Jenkins
Branch: liberty

commit 4c620fee1f509d15009fdc18c3ad53cac7bd5f69
Author: Jesse Pretorius <email address hidden>
Date: Wed Aug 3 14:40:41 2016 +0100

    Fix repo constraints construction and package installation

    The current repo build process has the following issues:

    1. The constraints consruction doesn't properly handle two constraints
       which use the same name, but have different version specs. eg:
       ovs===2.5.0;python_version=='2.7'
       ovs===2.6.0.dev2;python_version=='3.4'
       This is a problem in the constraints construction.

    2. The pip packages installed on the repo server in order to
       construct the repo do not respect the global pins or the upper
       constraint overrides.

    3. The constraints are selected based on the requirements specified.
       This makes the process unnecessarily complex.

    4. The global pins are not applied to the constructed constraints,
       so the wrong packages get built and installed.

    This patch corrects all of these issues and hopefully makes the
    mechanism for constructing constraints more readily apparent, and
    therefore easier to maintain.

    This backport combines selective changes implemented in the
    following reviews:

    - Add logic to NOT build "proprietary" packages
      https://review.openstack.org/300505

    - Updated py_pkgs to index requirement files
      https://review.openstack.org/345448

    - Fix py_pkgs lookup to not include optional packages
      https://review.openstack.org/347834

    - Update py_pkgs to itemise global pins
      https://review.openstack.org/347930

    - Fix repo constraints construction and package installation
      https://review.openstack.org/350352

    - Correct global_pins depth
      https://review.openstack.org/350654

    Change-Id: If52d073d43081468e2faf2cd063c4b211c29994f
    Related-Bug: #1605846
    Closes-Bug: #1609056