Switch to oslo.config generator

[Boris Pavlovic]

Make in rally similar patch to this:

https://review.openstack.org/#/c/126956/1

PLEASE MAKE A CHANGES just in tox.ini and tools

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/152847
Committed: https://git.openstack.org/cgit/stackforge/rally/commit/?id=387dc356e3792f5cf24145bf381c0c30268a9e02
Submitter: Jenkins
Branch: master

commit 387dc356e3792f5cf24145bf381c0c30268a9e02
Author: Andrey Kurilin <email address hidden>
Date: Wed Feb 4 12:23:08 2015 +0200

    Remove all non-incubated oslo code

    Rally repository includes openstack.common module with modules from
    oslo-incubator(modules are listed in openstack-common.conf file).

    All those modules can be splitted by 4 categories:
     1. logging modules
     2. aas related modules
     3. cliutils
     4. config

    Modules from first category were graduated to separate lib, so we can remove
    them and use `oslo.log`.

    Modules from second category are not really used and will be not used,
    because Rally-as-a-Service will use flask microframework instead of
    pecan(modules from oslo-incubator are designed for pecan).

    Since oslo core team did not plan to graduate `cliutils` module from
    oslo-incubator, so there are no reasons to sync this module with oslo, we
    can copy needed functions and maintain them in our repo.

    Additional to rally.openstack dir, modules from oslo incubator are located
    in tools dir.
    tools/config modules works pretty bad, opts from rally.osclients always lost
    during automated config generator.
    `oslo.config` lib provides a better way to autogenerate config sample of
    Rally. It requires new entry point, which returns a list with all opts(look
    at 'rally.common.opts', 'setup.cfg' for more details). Since all opts are
    used in one place, their names were unified.
    Also config was updated(via `tox -egenconfig`).

    tools/rally.bash_completion file is moved to etc dir, because etc dir
    corresponds better and it gave us ability to remove whole tools dir

    Closes-Bug: #1378960

    Change-Id: Ic127269c367275d3adcfc9f40d9144fce8295391