Add Songsterr

[leocaseiro]

I was wondering how would you feel, if we add the songsterr, as another provider?

They have an API to search by artist:
https://www.songsterr.com/a/ra/songs/byartists.json?artists=beatles

However, I don't know how to filter by song name.

The API also filters by the instrument which would be a nice feature to add:

https://www.songsterr.com/api/songs?size=50&pattern=jude&inst=drums

To download .gp* files, we need to read from the JSON based on the id.
https://www.songsterr.com/a/ra/player/song/{revisionId}.plist?apiVersion=2

Eg: https://www.songsterr.com/a/ra/player/song/2573.plist?apiVersion=2

I can only see the latest tab version for download via API, but it should be good enough.

[mlhoutel]

Of course, it would be nice to have an additional api.

For the ones that are currently supported, I'm not sure that a track search by instrument is possible. We will have to rework this part of the application which I find a bit clumsy at the moment.