Changes:
* Add support for a property, `IsAspNetCoreApp`, in the .csproj file of assemblies which are part of the shared framework.
* Remove unused dependencies
* Remove reference which have become part of 'netcoreapp3.0'
- #3754
- remove `#if`'s for multi-targeting where source is never multi-targeted
- left `StreamPipeReader`, `StreamPipeWriter` and their test classes alone because they're moving to CoreFx
* Replace the aspnet/JsonPatch git submodule and merge the master branch of its source to this repo
* Likewise for aspnet/DotNetTools
* And aspnet/HtmlAbstractions
* merge latest infrastructure changes from the release/2.2 branch
This changes DataProtection to build as projects instead of a pseudo-submodule. It replaces Package and ProjectReference with <Reference> items which custom targets then resolve.
* Pair implementations and unit tests side by side in src/ and test/ folders
* Update .sln and project paths
* Rename unit test projects from Test.csproj => Tests.csproj
* Update KoreBuild properties to allow building projects, not solutions
Justin Kotalik
Hao Kung
Nate McMaster
Pavel Krymets
Doug Bunting
Chris Ross
Nate McMaster