Introduce useDevelopmentLanguageDefaults option

[scaio]

The problem this PR is trying to solve:

https://github.com/mac-cain13/R.swift/issues/563

What this PR does:

This PR introduces a new flag use-development-language-defaults which when passed will cause the NSLocalizedString macros to have the value: option set to the translation value in the developmentLanguage if such a value is available and we are not using base localization.

Testing

• I could really use some insight on how to properly unit test this behavior.

End notes

First time opening a PR, please let me know if I missed something. I love this project and use it in pretty much all my apps. I think it would be great to have this functionality but please let me know if you think otherwise :)

[dphov]

@mac-cain13 Do you planned to include this feature to project?

[snowman647]

@mac-cain13 would be nice to have this feature.

[ghost]

It would be great if this makes into new release! Please take a look 🙏

[mac-cain13]

If this makes us work more like Apples own API I would include this, but I think we're in line with NSLocalizedString now. We can discuss this further in https://github.com/mac-cain13/R.swift/issues/563