[Merge] ~dbungert/livecd-rootfs:ubuntu-mini-iso into livecd-rootfs:ubuntu/master

[Michael Hudson-Doyle]

Review: Approve

So I still think we should have a .disk/info on the ISO but otherwise this lgtm and can land when mini-iso-tools gets promoted.
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https://code.launchpad.net/~dbungert/livecd-rootfs/+git/livecd-rootfs/+merge/436420
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