General format for command 'delete':
    vitis delete -action <data1> [flags]


vitis delete -v <file> ... [--all-links | -A] [--note | -N]
    The command deletes the specified files (hard links), whose paths
    are given relative to the root of the Vitis filesystem.

    Additional flags:

    --all-links | -A
        Removes all hard links to the specified files
        from all categories.

    --note | -N
        With this flag, only the note attached to the file deleted.


vitis delete -v <file> ... -с <category> ...
    The listed files will lose the specified categories.
    If the '--over' flag is specified, all parent categories will be
    taken into account during deletion.

    Examples:

        vitis delete -v "Documents/Pluto.pdf" -c "Planets"
            The hard link to "Pluto.pdf" will be removed
            from the "Planets" category.

        vitis delete -v "Programming/C/KnR.pdf" -c "Programming" --over
            The hard link "Programming/C/KnR.pdf" is removed
            because the '--over' flag is used.
            Without it, "KnR.pdf" would have to be located directly
            in the "Programming" category (for deleting).


vitis delete -v <file> -r <relation>
    The command deletes file relation.

vitis delete -c <category> ... [--all-links | -A] [--note | -N]
    The command deletes the specified categories even if they are not empty.

    Additional flags:

    --all-links | -A
        If this flag is set, the command will remove all hard links
        to the specified categories, if they exist.

    --note | -N
        With this flag, only the note attached to the category is deleted.
