[Merge] ~toabctl/livecd-rootfs:bionic-repostamp-backports into livecd-rootfs:ubuntu/bionic

[Thomas Bechtold]

iptables-legacy is not available in bionic. This change might not be needed. I'm currently retesting.
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https://code.launchpad.net/~toabctl/livecd-rootfs/+git/livecd-rootfs-1/+merge/409292
Your team Ubuntu Core Development Team is requested to review the proposed merge of ~toabctl/livecd-rootfs:bionic-repostamp-backports into livecd-rootfs:ubuntu/bionic.