python-novaclient should use volumes endpoint instead of extensions

[Vish Ishaya]

Now that nova-volumes has its own endpoint, python-novaclient should use it. Eventually these will move into a volume specific client.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/4481

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/4481
Committed: http://github.com/openstack/python-novaclient/commit/03f54c57e13f27324f0ac5aa556bf4ca94e3ed0e
Submitter: Jenkins
Branch: master

commit 03f54c57e13f27324f0ac5aa556bf4ca94e3ed0e
Author: Vishvananda Ishaya <email address hidden>
Date: Fri Feb 24 02:30:48 2012 +0000

    Makes novaclient use the volumes endpoint

     * Depends on https://review.openstack.org/#change,4479
     * Adds support to change service type including tests
     * Adds decorator for methods that need to use another service type
     * Changes volume and snapshots to use the volume endpoint
     * These extensions will move into the volume client once it exists
     * Fixes bug 940017

    Change-Id: I683e4ca6c67e278d8aa8a9acec3dc0f1872f43f2