This reverts commit c944301b.

Moving creation of chroot.files manifest in lb chroot after pseudo-filesystems have been unmounted to avoid loops, thanks to Michal Suchanek <hramrach@gmail.com>.

Sorting kernel versions in reverse order (newest first) in syslinux configurations in consistency with normal bootloader behaviours.

Adding hook to disable 70-persistent-cd.rules udev rule to prevent udev remember the cd device name both the one of the build system and the one of the live system (Closes: #706926).

Renaming remove-udev-persistent-rules.chroot hook to remove-udev-persistent-net-rules.chroot for future additional udev hooks.

Updating derivatives archive-key signature validiation to look by default at both debian and debian-maintainers keyrings.