Add "Simplified Chinese" language support

[bootlegseahorse]

zh-Hans.lproj.zip

I only translated the strings in Localizable.strings in YogaSMCNC. I planned to translate the preference pane too, but wasn't able to find the relative strings to translate.

[zhen-zen]

Thanks for the translation. For now, only NC supports localization since it's a pure swift app written from scratch. Do you want to raise a PR?

However, for prefpane there're few examples and it's put up to just accomplish basic tasks. All UI elements are static including the text. Currently I don't have an idea for future redesign.