Sort field content alphabetically with external workaround for missing $sort function

[ohrenkino]

I don't want to be a feature creep ...
Looking at this suggestion

Suggestion - Sort function for multivalue tag-fields

I think that Mp3tag needs a sort function (ascending, descending) for sorting a multivalue meta tag-field. DD.20100830.0849.CEST

the function is missing (very hard word) the switch for ascending or descending sort order.