fix artists metadata

[AldeToro]

Fix for artists names in metadata to resolve issue #115

Modified filename to have album's artist name instead
Modified ID3v1 artist metadata for album's artist (main artist) instead of song's ART_NAME value
Modified ID3v2 album's artist metadata for album's artist (main artist) instead of song's ART_NAME value
Modified ID3v2 artists metadata for a concatenation of all artists of the song

(It's my first pull request ever, yay \o/)

[kmille]

Can you give me a song where the PR fixes the problem. I also had problems in the past (#110)

[AldeToro]

You can use the one used in example in the issue #115
Scooter - My Gabber / https://deezer.page.link/Hr4uE6ewKMLxkMaR7

[AldeToro]

I also changed the used deezer URL from german to english because some artists names were translated to german

[kmille]

Hey
sorry I never found to really dig into this. I just merged #201, which is an updated version of your PR (resolves current conflicts). Now the filename problem is solved. Your MR also updates the ID3 tags. I will keep this open and try to inlucde your changes in the future. Feel free to rebase if you find time, but I rewrote this piece of code a lot. Now a library is used to write the metadata to disk.