Remove more stuff from /var/lib/systemd on systemd purge.
Add support for rcS.d init scripts to the sysv-generator.
Do not order rcS.d services after local-fs.target if they do not explicitly depending on $local_fs.
Map init script dependencies on mountall, mountnfs and cryptdisks to the corresponding systemd targets
Prevent rcS.d services from depending on remote-fs.target or network-online.target.
Order rcS.d init scripts before basic.target instead of sysinit.target.
Add breaks on old syslog providers, they interact badly with the journal.
Add breaks on old resolvconf, it interacts badly with systemd-resolved.
Bump dependency on sysv-rc for updated update-rc.d.
Do not force-enable default-on services on every upgrade.

Also drops the systemd-networkd, systemd-resolved and systemd-timesyncd
from the set of default services, but restarts them during an upgrade
if they were already running.
Enable networkd, resolved, and timesyncd by default.
Enable persistent journald logging by default.
Make systemd and systemd-sysv required packages.
Release to Tanglu staging.