[Merge] ~codyshepherd/livecd-rootfs/+git/livecd-rootfs:tarball-transform into livecd-rootfs:ubuntu/xenial

[Cody Shepherd]

Furthermore, these changes bring auto/config in line with what is currently in the ubuntu/bionic branch.
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https://code.launchpad.net/~codyshepherd/livecd-rootfs/+git/livecd-rootfs/+merge/392066
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