Add filter function to pagination logic and use it in playlists

[Skycoder42]

This PR is a followup to the discussion in #218. It follows the second approach described there that uses a filter function instead of returning nullable track objects.

I decided to create a 2nd PR so both approaches can be discussed and evaluated before a decision will be made.

[rinukkusu]

@Skycoder42 Looks good - would you be willing to also add a unit test for this new feature?

@hayribakici ❤️🤝 hehe