Confconsole - "usage" should also include option to "shutdown"

[JedMeister]

As suggested in the forums (initially hinted by Ian, then explicitly suggested by Carlos) it would be good to provide a "shutdown" option on the Confconsole "usage" screen.

The way it is now, a user needs to log in to shutdown which seems pretty dumb in retrospect!

[OnGle]

This is a non-issue in my opinion. Shutting down is the ultimate DOS, in addition to the fact that adding stuff to the usage screen is a little difficult, in my mind we should tag this as wont-fix. Unless there's a sufficiently convincing argument beyond mild inconvenience.

[JedMeister]

Hmm, you do raise a good point @OnGle...

What about we use the full Confconsole and if not already logged in, authenticate the user?! I just noticed that in Buster there is a Python3 PAM module - see python3-pampy.

I also moved this to 16.1 milestone.

[JedMeister]

Closing in favour of new issue: #1562