Additional PackageReference Nuget packages

[amaitland]

New packages will only support the PackageReference format (VS2017/2019 will be required to use them).

• [ ] Use the newer runtimes\native nuget feature for new cef.redist.win-x64/cef.redist.win-x86
• Restructure packages to only copy CEF resources using targets file
• Set minClientVersion to Nuget version supported by both VS2017/2019 (make it impossible for older versions to install the packages)
• Create CefSharp.WinForms.x86/CefSharp.WinForms.x64
• Create CefSharp.WPF.x86/CefSharp.WPF.x64
• Create CefSharp.OffScreen.x86/CefSharp.OffScreen.x64

There won't be AnyCPU support initially, the older packages will need to be used for that.

References

• https://docs.microsoft.com/en-us/nuget/create-packages/creating-a-package#including-msbuild-props-and-targets-in-a-package
• https://docs.microsoft.com/en-us/nuget/create-packages/supporting-multiple-target-frameworks
• https://docs.microsoft.com/en-au/nuget/guides/create-uwp-packages#adding-the-native-implementation-libraries

[TonyValenti]

Just wanted to let everyone know I'm looking forward to .NET Core 3.0 being fully supported!

[matthias-hoste]

If help is needed with this then I'd gladly help out as I'm really looking forward to this feature

[amaitland]

Pull Requests are welcome, finishing cefsharp/cef-binary#83 is step one.