Merge branch 'master' into issue/403

app/controllers/concerns/paginator.rb

app/controllers/v1/feed_controller.rb

app/models/concerns/trackable.rb

app/models/curator_assignment.rb

app/models/learning_object.rb

app/models/submission.rb

app/models/user.rb

app/serializers/submission_serializer.rb

app/services/activities_filter_service.rb

app/services/learning_object_publisher.rb

app/services/search_service/collection.rb

app/services/search_service/learning_object.rb

app/services/search_service/user.rb

db/migrate/20190205121252_add_status_to_complaint_reasons.rb

...3_add_state_and_suspended_at_and_reactivated_a_to_user.rb

...igrate/20190225143721_create_join_table_search_subject.rb

...90226122727_create_join_table_educational_stage_search.rb

...te/20190226122759_create_join_table_object_type_search.rb

db/migrate/20190226131445_create_join_table_search_tag.rb

...90227115926_create_join_table_language_learning_object.rb