Gitaly Praefect - Pass through proxy package
Introducing a new component isn't without risks and true to GitLab values we should iterate towards the new component.
To do so the first iteration will only be a pass through proxy, where the coordinator, for the time being called praefect, doesn't add or remove anything from any request.
To fix this issue, a well tested proxy package suffices to improve parallelizing the work in our team. An actual execution path, thus a binary to execute, is added by another issue.
/cc @pokstad1
P.S. Praefect is choosen because of the following quote:
a person appointed to any of various positions of command, authority, or superintendence, as a chief magistrate in ancient Rome or the chief administrative official of a department of France or Italy.
Open to suggestions though!