migration fixes and notification

fixes #1416  (includes it); and handles changing colorCommentScore non-default values to the appropriate enum value; and shows notification  if colorCommentScore option was updated from false to none on upgrade (to remedy's 4.5.0.1 failure to do so)

waits until body is ready to show notifications
am I dense / lacking sleep?

i can't see where notificationOpened would ever be set to true?