* Remove non-portable Linux nuspec files
* Remove non-portable macOS nuspec files
* Update runtime.json to reference **only** portable nuget packages
* Add portable macOS runtime.osx-x64.Microsoft.NETCore.CoreDisTools.nuspec
* Add portable Linux nuspec files
* Add win-arm and win-arm64 nuspec files
* Update win-x86 and win-x64 .nuspec
* Update Microsoft.NETCore.CoreDisTools.nuspec
* Address Bruce's feedback - setlocal EnableDelayedExpansion EnableExtensions in build-coredistools.cmd build-tblgen.cmd
* Check for cmake.exe in the PATH before running it in build-coredistools.cmd build-tblgen.cmd
* Define StagingDirectory in build-coredistools.cmd build-coredistools.sh
* Address Bruce's feedback - check the return code for all 3 cmake invocations in build-coredistools.cmd build-coredistools.sh
* Make TargetOSArchitecture values the same as .NET RIDs in build-coredistools.cmd build-coredistools.sh
* Change error message in build-coredistools.cmd
* Add pack-coredistools.cmd
* Update coredistools.yml
* Simplify build-coredistools.sh and strip debug symbols
* Use in non-cross-compiling scenario in build-coredistools.sh