readme.md for project should be updated to point at latest information for consuming Modern Windows APIs from .NET

[philnach]

The readme.md for the project is outdated and doesn't contain information about later versions of .NET and how to consume Modern Windows APIs. This can result in compilation errors, runtime errors, etc. Search engines also point to this Website as a way of calling Modern Windows APIs.

Suggestion: update the readme.md to point to: https://github.com/MicrosoftDocs/windows-dev-docs/blob/docs/hub/apps/desktop/modernize/desktop-to-uwp-enhance.md. The documentation available there breaks down how to call Modern Windows APIs from various versions of .NET.