I found a method available for webob response
objects called response.json which allows the
content of a json response to be dumped and
encoded so that response.body can be set to
the json response. This functionality fixes
ranger cooperation with tempest, which was
broken due to switch to use of response.text
Change-Id: I0f708186edc7cd1719fc9d9c0b93d639be9f71dc