Commented Feature: [Feature]Split the controls of library [17736]

Split the controls of library in more libraries and create new nuget package for each library.
Comments: ** Comment from web user: kentcb **

Agreed: the current NuGet package is too coarse. My build was broken when I upgraded from 1.9 to 2.0 because of the inclusion of AvalonDock, which seems to include its own copy of Microsoft.Windows.Shell, which I reference separately as another NuGet package.

Please, please, create finer-grained packages with an overarching package for those that want all of the WPF extended toolkit. I think there should be a package for the grid, for avalon dock, for the core control set, and then one that pulls in all three.