Include Hackage revision (x-revision) in install output

It's now possible to modify .cabal files after the fact on Hackage to fix e.g. incorrect dependencies. It's important that we communicate to users that they're using an updated .cabal file, so we should include the revision number wherever we should the package versions. We could use either `foo-x.y.z.p-rn`, where `n` is the `x-revision`. An alternative that sets the revision a part a bit more is `foo-x.y.z.p (rn)`. I have a slight preference for the former, as it appears as one "unit". We could investigate what e.g. Debian does.

Start by locating the install-output code that formats package versions and the code that reads Hackage metadata. Trace where the x-revision value is available, compare the proposed version formats, and verify that install output consistently identifies revised .cabal files wherever package versions are shown.

Written by the indexing model from the issue text.