* Create standalone llvm-build
This builds off of work from @idavis that establishes a custom LLVM pipeline build.
The output is then used along with ClangSharpPInvokeGenerator to create custom .NET
wrappers around the resulting binaries. The native binaries are then packaged so they
can be used as a dev-dependency and pulled into the LlvmBindings package later.
* Add publish logic to llvm.yml
* Include generated C# in nuget package
* Use latest build images
* PR feedback updates
* Only trigger LLVM build for changes to LLVM build files
* Fix mkdir, remove dead code, rename Write-Vso
Stefan J. Wernli