updating all requirements.txt but also requests in requirements_for_tests.txt
using new flask json parser options, adding in a print on failing test
Fix etag feature test for new query response

The actual data has not changed, however, by default, jsonify
sorts the keys of the resulting json so the etag is different.
Merge pull request #149 from alphagov/pipper

updating all requirements.txt but also requests in requirements_for_tests.txt