[Merge] ~davidkrauser/livecd-rootfs/+git/livecd-rootfs:bootable-buildd into livecd-rootfs:ubuntu/master

[David Krauser]

Digging into the size differences, the most significant change comes from the following:

- Installing the linux-generic package pulls in linux-firmware and linux-modules-extra. Those packages add about 600 MB to the bionic image.
- These buildd images also contain a full toolchain for building packages (gcc, linux headers, extra libs, etc.) which adds a few hundred more MBs.
- These buildd images boot with an initramfs. The minimal images don't.
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https://code.launchpad.net/~davidkrauser/livecd-rootfs/+git/livecd-rootfs/+merge/373916
Your team Ubuntu Core Development Team is requested to review the proposed merge of ~davidkrauser/livecd-rootfs/+git/livecd-rootfs:bootable-buildd into livecd-rootfs:ubuntu/master.