A new opam-standard metadata file describing the alternate views on this repository

My primary concern is the requirement for behavior of these URLs. I believe that the 'browse' URL should point to the browseable package index and the 'upstream' URL should point to the primary branch's root. Perhaps 'browse' should point to a location that corresponds to the repo as a whole (incl compiler switches) and the 'upstream' should point to a branch-agnostic interface. These locations are more flexible but more onerous to use, however, as they require further metadata at those locations to get you to where you want to go.
Merge pull request #1119 from dsheets/repo

Repo Standard Metadata?