Handle multiple artists

[Stypox]

When there are multiple artists they are sometimes written with "&", ",", "and", ";" as separators. Those should be recognized and the artist tag should contain all the artists in a way that they can be recognized by music players.

On a side note, should "original by .." be shown for remixed songs? They create problems with not-unique artist names in music players. Maybe they could be considered as secondary artists and added to the artist list pointed out above?