Switch Nova/Tempest to use/test Cinder API v2

[OpenStack Infra]

https://review.openstack.org/220081
commit ae4ed6e4fae3fc7ca67004115c3b52f85cd61bfa
Author: Jesse Pretorius <email address hidden>
Date: Tue Aug 18 08:17:17 2015 +0100

    Switch Nova/Tempest to use/test Cinder API v2

    As per https://blueprints.launchpad.net/cinder/+spec/deprecate-v1-api
    the Cinder API v1 was designated as deprecated in Juno and was meant
    to be removed in Kilo, but appears to still be usable in Kilo.

    This patch configures Nova to use the Cinder v2 API instead of the
    v1 API.

    This patch configures Tempest to test both the Cinder v1 and v2 API's
    for now. Once the API is removed upstream we can change this.

    DocImpact
    Closes-Bug: #1481542
    Change-Id: I6513c07e1b5d5653b84ad0b2b490ac8451f2bdf1
    (cherry picked from commit 16d1a5150411eee9a9dd41e624d8b4e39fdf681c)