Add systemd Depends: on new mount and Breaks: on old uuid-runtime.

Also drop now-obsolete manpage patch.
Add breaks on old resolvconf, it interacts badly with systemd-resolved.
Add breaks on old syslog providers, they interact badly with the journal.
Order rcS.d init scripts before basic.target instead of sysinit.target.
Rework support for Debian-specific locale, keyboard and timezone conf files.

This splits the existing patches into separate patches for each indepenent feature.
Rework the semantics of restart job deadlock avoidance during early boot and shutdown.