[packages_opts] is inconsistent with the rest of the opts sections and can be deprecated

[Kirill Zaitsev]

packages_opts is a weird name, since all options are opts already. Moreover these options combine both engine and api options, which makes the group inconsistent.

1) we should deprecate packages_opts and issue a deprecation warning whenever an option from packages_opts is used
2) we should move engine-related options to engine section, client-related options to [murano] section (the same way heat/keystone/etc options work), and api related options to [api] section. This should be done with proper deprecation techiques.

This would also restore backward incompatible change introduced by https://review.openstack.org/#/c/274606/

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/292797

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/292797
Committed: https://git.openstack.org/cgit/openstack/murano/commit/?id=cdeaff8cc2aebc7efabba5efe2add81573002906
Submitter: Jenkins
Branch: master

commit cdeaff8cc2aebc7efabba5efe2add81573002906
Author: Kirill Zaitsev <email address hidden>
Date: Tue Mar 15 13:21:50 2016 +0300

    Deprecate packages_opts conf group

    Group 'packages_opts' has always been inconsistent, since it included
    'opts' into it's name and options in that group we related to both
    engine and api. This commit moves engine related options to [engine]
    group and api-related options to [murano] group.

    This restores backward compatibility with liberty configs, that included
    'load_packages_from' into [engine] group

    'packages_opts' is added to all the options moved as deprecated_group,
    thus retaining backward compatibility with old configs

    Change-Id: I00b6f06ec352de4b57baaa86da9155bb36bcc23a
    Closes-Bug: #1543027