Possible maloja fork support

[duckfromdiscord]

I sent an email in August about this topic but it might've gone to spam.

I'm considering forking Maloja and adding some of my own features. One of the first features I add will be a new, separate spot for identifiers that all clients can use since it'll be a part of the API standard. There are some more ideas I have in mind which include a "now playing" feature that will require changes on multi-scrobbler's side, and I can pull request those if needed.

I spoke to a couple of other active Maloja users who have said they will use my fork if I make one. But if changes need to be made on multi-scrobbler's side, there will have to be a fork of that too, and it will be tough to maintain both. Ideally, we could add a config flag for your maloja client that enables features from my fork. It seems that including new parameters that my new API changes would take causes warnings from the server, so it would be best to include even just a hidden and off-by-default option to send these parameters alongside requests.

[FoxxMD]

MS already does a bit of "if maloja version is X or Y" due to supporting pre-3.0 versions.

compare-versions handles semver with tags just fine so my recommendation would be to use a tag in your fork's versionstring that MS could use to determine if it should send additional fields in the api call IE versionstring = '3.2.3-duck' or something.