Add to the app the option to remove artists thats keeps on the library instead of full delete of all items

[ArreglarYTM]

I have a problem related to one artist that had a song previously, but currently no, it seems to be related a bug into YTM, also I make like to the song, but doesn´t dessapear from my artists library. ¿Could you implement that feature on the app?, ¿Google API support this option?
Thank you in advance.
Cheers.

[apastel]

Addressed in #78