Spotify: fetch artist names with correct localization

[phts]

Spotify API allows Accept-Language request header to receive correct Artist names, written in native language, instead of transliteration.

However spotify-web-api-node does not allow setting any request headers.

My pull request thelinmichael/spotify-web-api-node#507 seems never to be merged , due to inactivity of the author.

In my forked plugin, I am using my fork of spotify-web-api-node and it works as expected.

Before:	After:

I don't create any PRs here, because I suggest creating your own fork of spotify-web-api-node to have full control of it, and apply similar changes there. Plugin changes look like that: phts/NP-01_plugins@5ccc58a

[volumio]

Very nice find @phts !

Forked the lib as you suggested:
https://github.com/volumio/spotify-web-api-node

Looking forward for the PR to include this on the lib (and please update the package.json of plugin as well)

thanks!