[Merge] lp:~cloudware/livecd-rootfs/image-consolidation into lp:livecd-rootfs

[Dan Watkins]

These are the changes made for the image consolidation work agreed at the 16.10 cloud sprint; this code is currently being used to build yakkety cloud images.
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https://code.launchpad.net/~cloudware/livecd-rootfs/image-consolidation/+merge/297041
Your team Ubuntu Core Development Team is requested to review the proposed merge of lp:~cloudware/livecd-rootfs/image-consolidation into lp:livecd-rootfs.