[Mixitup MultiFilter] Diacritics mapping not correct for some Danish characters

[patrickkunka]

From a customer:

I am using the multifilter and cant see that there is a github page for that.

There is a bug in the translation of danish characters, ø å.

They should be translated to:
ø = oe
å = aa

Currently they are translated to o and a which gives wrong search results.

Hope this makes sence - otherwise please contact me :-)