Use config-generator.conf to generate config.sample file

[Eli Qiao]

We hard code configure options in tox.ini to generate Magnum config
sample file, and we keep this config sample file in our repository.

It is inconvenient for developer if the add/remove/change some
configuration options cause they need to take care about the
config.sample file.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/272872
Committed: https://git.openstack.org/cgit/openstack/magnum/commit/?id=022bba9c06b25dfc2742a25f72cfa0b685c02a04
Submitter: Jenkins
Branch: master

commit 022bba9c06b25dfc2742a25f72cfa0b685c02a04
Author: Eli Qiao <email address hidden>
Date: Wed Jan 27 09:59:15 2016 +0800

    Use magnum-config-generator.conf to generate Magnum config sample file

    We hard code configure options in tox.ini to generate Magnum config
    sample file, and we keep this config sample file in our repository
    before.

    It is inconvenient for developer if the add/remove/change some
    configuration options cause they need to take care about the
    config.sample file.

    This patch removes magnum.config.sample instead of letting admin generate it
    from magnum-config-generator.conf(picked from tox.ini).

    P.S. Make tox.ini cleanup since it is not a good idea we mess up tox.ini
    with configuration options.

    Closes-Bug: #1538374
    Change-Id: I80d019b5c98e0282cd0fe50fd4ad66286287e2cb

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/magnum 2.0.0 release.