Please fix this mess so that it's an actually easy to use project

The promise of GRPC is being lost for Dart because of the massively overly-complex process for this. This should be a dev dependency in pubspec.yaml and should be a single command with everything setup properly with a single command.

And it should include all of the libraries to make it work from google including empty, etc. transparently just working.

If .NET can do this on save of the proto file and it just works, there's no excuse for the mess that this is in Dart. (specifically on windows, but everywhere should be trivial and it isn't.)