adding test for user model default scope
removing  action from answer_sets_controller - it's not used, as the home_controller renders the form
WIP: adding `not_applicable` to answers, and filtering them from answer_sets
setting answer_set validation of `no others in last five minutes` to be only on create
disabling form inputs, and adding overlay when `not_applicable` is checked. Also adding validation to ensure at least one answer is given