* 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 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)
Javier Calvarro Nelson
Nate McMaster
Ryan Nowak
Steve Sanderson