Move utility functions to fjord_utils.js

* move getQuerystring to fjord_utils.js
* move setQuerystring to fjord_utils.js
* move format to fjord_utils.js
* add test (which I commented out because it causes problems)
* move feedback/static/js/init.js to fjord/analytics/static/js/init.js
  because it's full of dashboard-specific stuff

r?