Extend `filterMatches` framework

[andreavicini]

I have a doubt. Let's say e.g. we want the 3 best matches and the ranks are: 1 2 3 3 4. Having matches with exactly the same score maybe is not very likely but in that case should we return 4 matches or the first 3?

[jorainer]

I would only return the first 3, even if the some of the matches have the same score/rank. We should always at max return n matches, not more. But please mention that in the documentation.