Fix up the ora2 scores affected by the track changes bug.

  For affected assessments:
    - Sets PeerWorkflowItem.scored = 0 if currently = 1
    - Recalculates the score for the submission
    - If new score > old score, update the Score.points_earned with the new score
I'd like it if your doc strings (including package docs) had a one-line summary before the newline and everything else.

Also, these doc lines say that it does things, but it doesn't say why it does them or under what circumstances. I guess the instructions I asked you comment with could go here...?