dropbox/responses — pull request #45 by ticosax (2014-12-18 14:17:09+00:00)
Title: Raise if requests are not performed as expected

I expect from my testing tools to detect inconsistencies and unpredictable behaviour.
This is why I would like that `responses` helps me to detect request that has not been performed unlike it should.

I implemented it in a way that is backward compatible, but I'm in favour of enabling this behaviour by default.