Fix for date validation error TIM-575
Add uniqueness constraints for student training models; check for integrity errors
Merge pull request #336 from edx/will/uniqueness-and-integrity

Uniqueness constraints for student training
Make submission_uuid in StudentTrainingWorkflow unique
Merge pull request #335 from edx/will/tim-575

Fix for date validation error TIM-575
Merge pull request #337 from edx/will/one-more-uniqueness-constraint

Make submission_uuid in StudentTrainingWorkflow unique
Fix for TIM-572
Merge pull request #334 from edx/will/multiple-objects-error

Fix for TIM-572
Refactor JavaScript so self- and peer-assessment use OpenAssessment.Rubric
Merge pull request #338 from edx/will/refactor-rubric-javascript

JS rubric refactor
Upading the staff debug student info text and styles
Merge pull request #339 from edx/sanchez/small_student_info_tweaks

Upading the staff debug student info text and styles
Integrate the student training API with the XBlock.
Adding the Student Training UI
Add student training JavaScript
Separate Python and JavaScript install/test scripts
Adding a top-level message with instructions for student training
Fixup student training JS tests
Show new-style locations in course staff debug info (opaque keys update)
Define AI grading API.