Localization system enhancements

[hikalkan]

• ToSentenceCase if not found (optional)
• Wrap with brackets if not found (optional, we can enable in development time for example)

[kanadaj]

@hikalkan What's the stance on allowing localization files to contain structured JSON (to be flattened at runtime with some delimiter such as a colon) instead of strictly key-value pairs? From what I've seen this currently throws an exception, but might be useful in use cases where strings can be easily categorized into smaller categories.

[hikalkan]

Thank you for the suggestion. It seems reasonable, but we should think on it more. I don't see that's a high priority thing, but will consider in the future versions.