ember quiz moderate display/update unfinished time

closes CNVS-12915

display estimated running time, or countdown for timed quizzes, and
clock icon within quiz moderate display when a quiz submission has
been started, but not finished. also auto refreshes the moderate data
after 1 minute, and then again every 3 minutes after that.

 test plan:
  - enable ember quizzes

  - scenario 1
    - as a student start, but do not complete a non-timed quiz
    - as instructor navigate to ember quiz moderate for the quiz
      - time column should display clock icon and estimated time
      - estimated time should update, displaying time student has been
        taking the quiz
    - as student complete and submit the quiz
    - as instructor refresh the page, or click refresh icon
      - student row in moderate page should update, remove icon

  - scenario 2
    - repeat scenario 1, but for a timed quiz
      - in moderate table, time should update
        - time should be counting down with students remaining time
        - if time reaches 0, it should:
          - stop displaying clock icon
          - stop counting down
          - display amount of time taken on the timed quiz

  - for due_at and locked_at quizzes, behavior should mimic
    scenario 1. clock stopping for due at, lock at will be addressed
    in CNVS-13151

Change-Id: If4b50f74a895f29ba89a56cecb04dca44ecc6c6f
Reviewed-on: https://gerrit.instructure.com/34845
Reviewed-by: Derek DeVries <ddevries@instructure.com>
Tested-by: Jenkins <jenkins@instructure.com>
QA-Review: Nathan Rogowski <nathan@instructure.com>
Product-Review: Jason Madsen <jmadsen@instructure.com>