WIP - added a middleware to dump all requests info into the stdout

I suggested this to Benson, but he said it was simpler for him to just plug the output to circus' rotating log. That what is done in FxA. I asked Rob: what happens when Heka get a non-json line can it be ignored ? he said yes.

So I suggest that we just keep it this way for now and see with Benson to improve it globally across project