1.9.9 - NuGet Visual Studio 2019 Support

This release is the last 1.9.x release fixing just one issue.
Now it is possible (again) to use the cpr NuGet package in Visual Studio 2019.

What's Changed

• Fix/vs19 nuget compatibility by @COM8 in #1160

Full Changelog: 1.9.8...1.9.9