Issue #2374297 by thehong: Rename QUESTION_* to QUIZ_QUESTION_*
Issue #2288689 by jhedstrom, idebr: Don't provide custom display settings for 'Question' view mode by default
Removed legacy constant.
Issue #2328803: fixed issue where choice_penalty is not saved
Issue #2328803: Matching needs tests
Updated readme/changelog/developer/install.
Issue #2379099 by djdevin, mrded: Cannot view 'my results'
Issue #2373395 by djdevin: Add a "builds on last attempt" functionality
Preserve tab contexts on quizzes.
Removed old doxyfile.
Merge branch '7.x-5.x' into 5x-travis

* 7.x-5.x:
  Removed old doxyfile.
  Preserve tab contexts on quizzes.
  Issue #2373395 by djdevin: Add a "builds on last attempt" functionality
  Issue #2379099 by djdevin, mrded: Cannot view 'my results'
  Updated readme/changelog/developer/install.
  Issue #2328803: Matching needs tests
  Issue #2328803: fixed issue where choice_penalty is not saved
  Removed legacy constant.
  Issue #2288689 by jhedstrom, idebr: Don't provide custom display settings for 'Question' view mode by default
  Issue #2374297 by thehong: Rename QUESTION_* to QUIZ_QUESTION_*