Inline Analytics

  Display of answer distribution graphics inline on the problem page
  for instructors.

  Problem types supported for graphics:
    - MultipleChoiceResponse
    - ChoiceResponse

  Problem types supported for line item display:
    - OptionResponse
    - NumericalResponse
    - StringResponse
    - FormulaResponse
    via setting

Internal review only for now.
Missing semicolon.

While you're at it, this line split (and others like it) look "weird"
and still end up wrapping on my screen. For most everywhere, it'd be
nice to see splits extended, putting each argument on its own line.