Support for Icelandic

[PallHaraldsson]

Hi, I could add the needed words, if it makes sense.

FYI:

https://www.pinhok.com/kb/icelandic/386/icelandic-grammar/

Icelandic does not have an indefinite article (a/an in English), and the definite article (the) is usually added onto the end of the word.

There's are exceptions, "hið" (or "hinn", "hin" depending on gender) for something very formal, we very rarely use those, except e.g. "Hið háa Alþing" for "The mighty Alþing"/parlament. We might alternatively say Alþingi with the -i ending there for definite article.

I didn't look enough into the package to know if useless to add. Maybe this package is helpful for somebody for those other words where it applies, but we have on average over 20 word forms, so the vocabulary is over 6 million word forms.

Trivia:
Adjectives have on average 89.1 (1-227 forms depending on the word) and verbs on average 95.7 (1-199), and the definite article 24 forms. Statistics for all words here:
https://bin.arnastofnun.is/b-daemi/

See here for example word for "horse", nouns typically have 16 forms, 4 plus the 4 with the definite article ending "með greini", and then again for plural (sometimes, as here, but not always, all distinct):
https://bin.arnastofnun.is/beyging/6179

Or the definite article as a separate word:
https://bin.arnastofnun.is/leit/beygingarmynd/hi%C3%B0

[aviks]

Would be good to get a PR for this?