* Fixes multiple issues that happened due to the E2E tests not running on the CI
* Enforces prerequisites for E2E tests on the CI and when building projects with E2E tests.
* Re-enables the E2E tests for templates.
* Update build.cmd to install .NET Core into $repoRoot/.dotnet instead of $repoRoot/.dotnet/x64
* Move restore sources from build/sources.props into eng/Versions.props (following arcade conventions)
* Remove usages of RuntimeFrameworkVersion in tests and build
* Update Blazor VSIX to use Arcade VSIX tools
* Rename Common.Tests to IIS.Common.TestLib and make it a test asset
* Remove custom versions props for ANCM installer code
* Remove duplicate references to xunit and remove usages of IsTestProject
* Remove duplicate references to Internal.AspNetCore.Analyzers
* Import Arcade.Sdk props and targets and remove custom versioning props
* Remove references to Internal.AspNetCore.Sdk
* Rename PackageLicenseType => PackageLicenseExpression
* Remove dependency on tasks in Internal.AspNetCore.Sdk, add ref to Internal.AspNetCore.BuildTasks as a temporary workaround
* Use Arcade's nuspec support
* Rename SignalR.Client.FunctionalTests to SignalR.Client.FunctionalTestApp
* Fixes for changes to property evaluation order
* Update BaseLineGenerator to netcoreapp3.0
* React to changes in evaluation order in RPM files and quirks in using <Exec> instead of <Run>
* Update Microsoft.Extensions.ApiDescription.Server to react to changes in Arcade packaging
* Workaround aspnet/AspNetCore#11009
Update the build scripts to support building subfolders or subgroups of projects
* Add build scripts for ci
* Remove obsolete scripts
* Add flags like --test and --pack to control running just test or packaging
* Add flags like --managed and --native to control building sub-types of projects
* Remove KoreBuild bootstrapper flags
* Update to extensions 3.0.0-preview.18619.1 (needed to get a fix for aspnet/Extensions#815 to make this change work on MSBuild.exe)