Merge branch 'issue/388' of https://gitlab.c3sl.ufpr.br/portalmec/portalmec into issue/388

app/controllers/v1/learning_objects_controller.rb

app/models/learning_object.rb

app/models/review.rb

app/serializers/learning_object_serializer.rb

...90227115926_create_join_table_language_learning_object.rb

lib/tasks/language.rake

spec/acceptance/learning_objects_spec.rb

spec/factories/learning_objects.rb

test/fixtures/learning_objects.yml

test/models/learning_object_test.rb