Add Debian Proper

[Zorgodon]

I think there ought to be separate category for distros which install with systemd by default, but can use other init systems without any problems. For example,

# apt-get install sysvinit-core sysvinit-utils
# reboot
# apt-get remove --purge --auto-remove systemd systemd-sysv libpam-systemd

Effiectively gets rid of systemd on Debian proper and the system works fine on sysvinit. The packages above can be pinned in /etc/apt/preferences.d to prevent them from being installed again. OpenSUSE also appears to have sysvinit-tools.