MacOS mojave getAvailableDictionaries does not find all dictionaries.

[AdamChlupacek]

Hello,

I have started to use this library in my electron application, and I found that calling getAvailableDictionaries does not give me all dictionaries those included in ~/Library/Spelling.

I have found out that the call availableLanguages on NSSpellChecker does not return the dictionaries, but when I try to code small swift app that calls NSSpellChecker.shared.availableLanguages it returns all the dictionaries.

Is there any way how to fix this please?

MacOS: 10.14.4
node-spellchecker: 3.5.2

Seems that #42 has a possible fix, but not sure about its validity.