Migrating to simpler user experience: reduced search form to single entry box
WIP: search action from index page
Interim step: basic search operation
Switching back to multiple form layout
Basic workflow from search to preview, non-JS
Added date selectors for non-JS case
Updated to new version of data services API with search capability
Some refactoring and tidying up on basic JS-less workflow
Tests on UserPreferences
Tests on data_service base class
Minor refactoring
Integration testing