When building with debootstrap, debootstrap will use the key to check
that everything is properly signed. It will not `apt-key add` the key
into the final environment, however.
Early adding the key after debootstrap before we need to read from the
private repo again prevents unsigned issues. This also maintains the
integrity of the packages in the environment throughout the build.
Change-Id: I5ca75ae4620c9fb26b512cb30f8cd79fa7a0373a
Debian Stretch released as stable recently, and the init system is
less tightly specified in the base dependencies (for some info, see
[1]). It seems, probably unintentionally, that in the previous
release systemd-sysv was brought in by debootstrap, but that is no
longer happening.
Add systemd as an early dependency of debian-minimal.
Remove the package-installs.yaml as that happens too late (other
things need to know the init system to write out service files, etc
and probe for systemd utils before package-installs). As mentioned, I
do not believe the "only install systemd on testing" idea was actually
working here, because it was being brought in during the initial
debootstrap.
Update some documentation to explain what's going on
[1] https://lists.debian.org/debian-boot/2015/05/msg00156.html
Change-Id: Id67c0cf08728407d234976f9807d3bd71d12f758
