Merge branch '175_relationship_resolver' into unofficial_release

* 175_relationship_resolver:
  Fix RelationshipResolver to examine provides as well.
No-op: Merge branch 'unofficial_release'

This is a no-op, everything in the unofficial release branch from a
month ago is already in master. However this gives us git history that
allows us to verify that, meaning I can happily get rid of the branch.

(Yes, I spend a lot of time on `git branch --no-merged` spotting what
things may have been written but we've missed.)