Add basic Chinese localisation support

[tboby]

The file to translate can be found here https://github.com/cwtools/cwtools-vscode/blob/localisaiton/release/package.nls.json

While it's technically possible to preview this in VS Code, I think it's probably too much work for this set of strings, which I think should be translatable with a little context.

[tboby]

@textGamex If you can organise the translation of that file, and provide that context to the translators, I should be able to just drop it in to the next release.

[tboby]

I'd also accept any improvements to the English if you think anything is very unclear :)

[tboby]

It's also worth noting that the settings hierarchy cannot be translated, so it'll always have the english bits here: