Merge branch 'submission' into 'master'

app/controllers/concerns/publisher_controller.rb

app/controllers/v1/learning_objects_controller.rb

app/controllers/v1/questions_controller.rb

app/controllers/v1/submissions_controller.rb

app/models/answer.rb

app/models/curator_assignment.rb

app/models/question.rb

app/models/submission.rb

app/models/user.rb

app/policies/application_policy.rb

app/policies/learning_object_policy.rb

app/policies/publisher_policy.rb

app/policies/question_policy.rb

app/policies/submission_policy.rb

app/serializers/question_serializer.rb

app/serializers/submission_serializer.rb

app/services/activities_filter_service.rb

app/services/curator_assignments_service.rb

config/routes.rb

config/schedule.rb