Add Luxembourgish localisation

[igotinfected]

This PR includes Luxembourgish localisation based on a mix of implementations for different languages (i.e. German, French, Icelandic, ...). The most annoying part is dealing with the Eifeler Regel, where an n must be removed from a word based on a number of factors (punctuation, location within sentence, and most importantly, the first letter of the following word).

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[igotinfected]

Hey 👋🏼 @clairernovotny @hazzik

I would like to integrate Humanizer into our internal tools, it would be ideal to have Luxembourgish included when I do (we usually support the 4 major languages, English, French, German, and Luxembourgish). Would you be able to provide me with a very approximate ETA on if/when this could be merged and released? I'm not in a major rush -- just seeing as the last release dates back a year I'd like to have an idea of whether I should look into publishing something privately for our use-case 😉

[SimonCropp]

@igotinfected can you rebase

[igotinfected]

@igotinfected can you rebase

Done! Struggling with some Fr and He tests failing locally randomly, don't think it's related to my changes though.

Big thanks to you and everyone involved for reviving the project :)

[SimonCropp]

thanks

Struggling with some Fr and He tests failing locally randomly

yeah i have not worked out the cause of those. and not related to your changes