Add a lock option

[jgranduel]

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Summary

CLI should display a mean to lock the vault

Motivation

New to Cryptomator and happy to see there is an official CLI.
But CLI help is a bit terse. It would be nice to display how to unmount the drive and close/lock the vault. I haven't tried on Linux/Mac, but on Windows, there remains a zombie mounted drive. A clean way to lock should be displayed in my opinion :-).

Considered Alternatives

No response

Anything else?

No response