Now v2 API uses code from v3. It's confusing and logically incorrect.
This patch makes v3 API as an extended version of v2.

The next patches related to this bug duplicated code between v1 and v2,
v2 and v3 will be removed.

Change-Id: I90a2b713556e91db69270a03ef6b798e08f93f90
Partial-Bug: #1643584

Add support for Cinder API /v3 endpoint.
A couple of unit tests for /v3 endpoint were added to v3/test_shell.py
to ensure that the v3 shell works, and to also test that modules work
with:
from cinderclient.v2.availability_zones import *
syntax.

Change-Id: I6ae0ada221bebb4ab1850d9c99b10fcbb585201f
Implements: https://blueprints.launchpad.net/python-cinderclient/+spec/add-v3-endpoint-support

Change string representation of VolumeBackupsRestore to use
volume_id rather than non-existent VolumeBackupsRestore id.

Change-Id: I7b585d0de9b3b0511e7fd1a70b214090a17dfa93
Closes-Bug: #1255488

ManagerWithFind requires list() method in its descendants.
Make it abstract and fix its improper descendants that do
not implement list() (QuotaSetManager and others).

Change-Id: I691ca389b5fea4c1bb36499a264b578fa825bbbf
Fixes: bug #1180393

Implements support for the volume backup api added to cinder in
https://review.openstack.org/19468. This is a resubmit of the
expired change https://review.openstack.org/25299 with the
following changes:

* Added unit tests for backups (v1 and v2)
* Changed references in backup code to display_name and
  display_description to name and description respectively
* Removed links from backup-show output
* Added object_count to _translate_backup_keys
* Removed unneccesary items from _translate_backup_keys
* Fixed backups docstrings including removing references to swift.

Adds backup-create, backup-delete, backup-list, backup-restore
and backup-show to both the v1 and v2 clients, since the volume
backup extension is available via both APIs.

Change-Id: I197384f1c2fd2af641d207a5f4dba0dfbc5c681a