* The LMS expects that all graded blocks define a 'max_score' method which
  returns the highest possible grade. In our case, the highest possible grade is always equal 1
* Grade information is now displayed beneath the display name of the
  problem (similar to CAPA).
* Display highest grade in feedback area. In assessment mode, display the highest grade that the student achieved
  in the feedback area. Do not display grade feedback when weight == 0.
* Store and publish grade even when zero (student attempt completely wrong).
* Explicit method for calculating learner_raw score.
* Renamed "Maximum score" field to "Problem Weight" to be in line with CAPA problems and avoid confusion.