Merge: mongo::queries: add unwind method
authorJean Privat <jean@pryen.org>
Fri, 10 Feb 2017 16:00:00 +0000 (11:00 -0500)
committerJean Privat <jean@pryen.org>
Fri, 10 Feb 2017 16:00:00 +0000 (11:00 -0500)
Also fix `op` method so it matches the specification in the comment

Pull-Request: #2362


Trivial merge