Can't disable force raw images

[Vish Ishaya]

The fix for: https://bugs.launchpad.net/nova/+bug/853330 does two things:

a) disallows backing files

b) forces all images to raw format

The first is a serious security issue. The second helps with performance, but can lead to issues for deployers. It forces large disks when sparse images could offer huge space savings. It is especially problematic for deployments using older code that are trying to upgrade.

It makes sense to have a flag for b) s that some deployments can continue to use compressed and/or sparse images.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/4143

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/4143
Committed: http://github.com/openstack/nova/commit/e48c252467b280986660d5ea8ed618f1ccf08d5d
Submitter: Jenkins
Branch: master

commit e48c252467b280986660d5ea8ed618f1ccf08d5d
Author: Vishvananda Ishaya <email address hidden>
Date: Tue Feb 14 09:03:18 2012 -0800

    Create a flag for force_to_raw for images

     * Allows for deployers to use compressed images if they prefer
     * Flag defaults to current behavior
     * Fixes bug 932180
     * Re-enables fetch_to_raw which was being skipped
     * Removes obsolete and broken method from libvirt
     * Checksumming will be re-enabled in a later patch

    Change-Id: I40c33cfd3997cae8d127fa45f8cf0aa071418170