Device-based gettys
Johan pointed out that the current one-file-per-getty configuration isn't very flexible, not to mention not very Upstartish; and there's a much better solution. Have a single getty job that spawns an instance for each terminal configured.
Spawn instance, and set goal to start, on the tty-added event; optionally matching the name of the tty to limit, e.g.
tty-added tty[1-6]
Set goal to stop on the tty-removed event; matching the first argument from the start event, e.g.
tty-removed $1
Instance can be destroyed once stopped; though this might not be desirable, since we might want to be able to start it again.
We'll need to keep the emission record for the start event as long as the instance is active.
This will almost certainly need to be combined with some other events or state, for example when there is a writable filesystem. These need to not mask out the tty events, which are the "prime" ones as far as this instance is concerned.