bug#34949: 27.0.50; Docstring of `vc-deduce-fileset' incomplete

[Juri Linkov]

>> In any case it seems the best default would be to include to fileset
>> all files except with the 'unregistered' status.
>
> What other statuses do you want to include except the two I mentioned?

I don't know all possible statuses.

>> Then the backend will
>> handle the files with the 'conflict' status (e.g. to signal an error).
>
> No, it won't signal an error. It will silently commit the changes.

Too bad.  This means we can't collect files into a fileset
behind the scene without user's consent.  The user should have
an overview of the fileset in VC-Dir before committing it.

Thus I'm going to implement this design: when a directory is marked
in Dired, then invoking 'C-x v v' in Dired will open the *vc-dir* buffer
and mark the same directory in it.