Volume type needs to be provided when creating a consistency group

[Xing Yang]

When creating a consistency group, the scheduler will find a backend that
supports all input volume types. If volume types are not provided, the
default_volume_type in cinder.conf will be used, however, this could cause
inconsistent behavior in a user environment where the default_volume_type
is defined in some places but not in others. This fix removed the use of
default_volume_type for CG creation, added a check to verify that
volume types are provided when creating a CG.

When creating a volume and adding it to a CG, we need to make sure a
volume type is provided as well.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/119564

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/119564
Committed: https://git.openstack.org/cgit/openstack/cinder/commit/?id=9082273305b0b9c117eb677a0e34c2ffde4e66f0
Submitter: Jenkins
Branch: master

commit 9082273305b0b9c117eb677a0e34c2ffde4e66f0
Author: Xing Yang <email address hidden>
Date: Sat Sep 6 13:32:02 2014 -0400

    Volume types need to be specified when creating CG

    When creating a consistency group, the scheduler will find a backend that
    supports all input volume types. If volume types are not provided, the
    default_volume_type in cinder.conf will be used, however, this could cause
    inconsistent behavior in a user environment where the default_volume_type
    is defined in some places but not in others. This fix removed the use of
    default_volume_type for CG creation, added a check to verify that volume
    types are provided when creating a CG.

    When creating a volume and adding it to a CG, we need to make sure a
    volume type is provided as well.

    Change-Id: I078d4fdd8d92529e853be16272ad74d1e130f712
    Closes-Bug: #1366371