collect unconverted yet upstart services for systemd

[You-Sheng Yang]

From https://wiki.ubuntu.com/SystemdForUpstartUsers there is a automatically generated page http://people.canonical.com/~jhunt/systemd/packages-to-convert/ that lists all the remaining packages to be converted. However, I think some things are missed, e.g. tty allocation in touch+upstart is disabled, but it's not in systemd yet. So we'll need some more effort to make sure the system is in a synced state first. Some investigation works are in need.