Add action taken to notices/show
Add action_taken to serialized Notices

Also update documentation re: action_taken in general.
Add action_taken to searchability
WIP
Modify fielded search spec to work with action_taken

Refactorings:

* FieldSearchNoticeGenerator was simplified for readability and now
  controls the query value itself (required for action_taken to work)

* FieldedSearchOnPage no handles sleeping itself