[Porting] Pycue to Golang

Hi All, due to several considerations, we decide to do porting all functions from pycue to golang.
basically by utilized python GRPC with golang.
We have managed almost everything, but still cannot figure out how to use LunchSpec and and also LunchSpecAndWait.
We cannot found what kind of XML contents to be fill in.

We planned to opensource these as well, in order to increase OpenCue adoption especially when combine with Kubernetes.

Any comments are welcome.

Start by comparing the existing pycue behavior with the Go gRPC port, focusing on the LunchSpec and LunchSpecAndWait entry points and the XML contents they require. Determine the request structure and expected waiting behavior before extending the port; done means these functions work in Go and the planned Kubernetes-oriented port is complete.

Written by the indexing model from the issue text.