[Merge] ~patviafore/livecd-rootfs/+git/livecd-rootfs:linux_kvm_image into livecd-rootfs:ubuntu/master

[Francis Ginther]

Review: Needs Fixing

Other then the unmount before creating the qcow2 image, this looks good. As rcj mentioned, this can lead to corruption and other unpredictable results. Thanks for picking this up.
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https://code.launchpad.net/~patviafore/livecd-rootfs/+git/livecd-rootfs/+merge/368350
Your team Ubuntu Core Development Team is requested to review the proposed merge of ~patviafore/livecd-rootfs/+git/livecd-rootfs:linux_kvm_image into livecd-rootfs:ubuntu/master.