Make nova baremetal support ephemeral disks

[Joe Gordon]

Right now nova baremetal just makes root and swap partitions, we want it to also create 'ephemeral partitions.' This is the first step in being able to rebuild a baremetal instance with a new image but preserve the data on the ephemeral disk.

We want the partition order to be: ephemeral swap root
We want root last, is that we put root at the start to stop it resizing so we could use all the space for a new partition, but this use of ephemeral makes that explicit. so instead having the extra space to allow root to resize will make it safer to do takeovernode with slightly larger images.

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/51326
Committed: http://github.com/openstack/nova/commit/48996af0f386a5087d99aacc7d7e5f7d0b7395fd
Submitter: Jenkins
Branch: master

commit 48996af0f386a5087d99aacc7d7e5f7d0b7395fd
Author: Joe Gordon <email address hidden>
Date: Fri Oct 11 17:43:49 2013 -0700

    Add ephemeral_mb record to bm_nodes

    As the first step in making baremetal support ephemeral partitions the
    baremetal db needs to keep track of the ephemeral disk size.

    Change-Id: I990f02a37799f4d9a3bde39a6058641a4a5314a4
    Partial-Bug: #1238311

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/51735
Committed: http://github.com/openstack/nova/commit/81d35f36e1dfdc02f55c5be3282d458f66e166a3
Submitter: Jenkins
Branch: master

commit 81d35f36e1dfdc02f55c5be3282d458f66e166a3
Author: Joe Gordon <email address hidden>
Date: Mon Oct 14 15:53:59 2013 -0700

    Make baremetal_deploy_helper understand ephemeral disks

    Teach baremetal_deploy_helper how to run sfdisk with ephemeral disks.
    baremetal_deploy_helper calls default mkfs on the epheral disk.

    Change-Id: I92d473c34e9a076f5dbcd54be538410b30b10204
    Partial-Bug: #1238311
    Co-Authored-By: Robert Collins <email address hidden>

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/65750

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/65750
Committed: https://git.openstack.org/cgit/openstack/ironic/commit/?id=c30f8b6fab1c288032fd25fd23deee1622680418
Submitter: Jenkins
Branch: master

commit c30f8b6fab1c288032fd25fd23deee1622680418
Author: Lucas Alvares Gomes <email address hidden>
Date: Thu Jan 9 18:31:47 2014 +0000

    Make the PXE driver understand ephemeral disks

    Allows the PXE driver to create an ephemeral partition. This is the first
    step in being able to redeploy a baremetal machine with a new image but
    preserve the data on the ephemeral disk.

    Based on Nova's patch: https://review.openstack.org/51735

    blueprint: preserve-ephemeral
    Closes-Bug: #1238311
    Change-Id: I2826f1f8b60316ea180284cffc495a7556e31784