Add supported languages

[robert00s]

Close #2645
All skipped languages have been added.

[houqp]

NIce, where did you get the mapping from language name to po file name? We might be able to automate this.

[robert00s]

Unfortunately in google translator :)

[retrue]

A small problem with the sorting of languages.
Rigtht now languages using the latin alphabet are sorted alphabetically by the language name in its own language, and all the non latin languages are sorted alphabetically by its international code (example, ko_KR for Korean).
That means that Greek "el" should be just before that Farsi "fa", and that Portuguese should be just before Portuguese do Brazil.
EDIT: And norsk should be Norsk.