* Simplify ref/ assembly generation
- followup 1/2 for 5266918ed2
- correct the Razor.Tools project
- `%(Reference.Version)` metadata does not bleed through into `@(PackageReference)` items
- much more work to do so than to add this special case
- remove `$(Razor_NewtonsoftJsonPackageVersion)`
- remove RTMVersions project and use RepoTasks instead
- make it an error if RepoTasks is not restored before anything else builds
- add items and properties for System.Security.AccessControl
nits:
- remove invalid (ignored) metadata in Directory.Build.props and AzureAppServices.SiteExtension project
- improve / extend a couple of comments
- move `@(Reference)` items together in Microsoft.AspNetCore.Razor.Tools
fb28ce3ec2