Update MP4 Album Artist tag support from upstream TagLib

[marade]

Thanks for all of your hard work on Nightingale. Because of recent updates to TagLib...

https://mail.gnome.org/archives/commits-list/2016-April/msg06644.html

...it seems that Nightingale can now be updated to properly support the Album Artist tag for mp4 files. This problem has been a known issue for years, e.g.

http://forum.getnightingale.com/thread-852.html

#65

Can this bug finally be addressed? The Album Artist tag is considered essential by many for music collections, because it allows (for example) compilations with multiple artists to be distinguished with the individual artist names in the Artist tag, and then "Various Artists" in the Album Artist tag. Then one can sort by Album Artist in players like Nightingale, and compilations will show up as distinct units, grouped together under Various Artists.

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[Thanatermesis]

Any update? or a working fork of nightingale? 🤔