Support .NET Core 3.1 (tdlib#838)

README.md

@@ -160,7 +160,8 @@ See [example/java](https://github.com/tdlib/td/tree/master/example/java) for exa
 <a name="using-dotnet"></a>
 ## Using in .NET projects
 `TDLib` provides native .NET interface through `C++/CLI` and `C++/CX`. To enable it, specify option `-DTD_ENABLE_DOTNET=ON` to CMake.
-.NET Core doesn't support `C++/CLI`, so if .NET Core is used, then `TDLib` JSON interface should be used through P/Invoke instead.
+And you can use native C++/CLI TDLib interface in .NET Core 3.1 (Only Windows)
+.NET Core Less than 3.1 doesn't support `C++/CLI`, so if .NET Core is used, then `TDLib` JSON interface should be used through P/Invoke instead.
 
 See [example/csharp](https://github.com/tdlib/td/tree/master/example/csharp) for example of using `TDLib` from C# and detailed build and usage instructions.
 See [example/uwp](https://github.com/tdlib/td/tree/master/example/uwp) for example of using `TDLib` from C# UWP application and detailed build and usage instructions for Visual Studio Extension "TDLib for Universal Windows Platform".