Merge branch 'modifications' into 'master'

app/controllers/v1/institutions_controller.rb

app/controllers/v1/licenses_controller.rb

app/controllers/v1/mime_types_controller.rb

app/controllers/v1/object_types_controller.rb

app/controllers/v1/ratings_controller.rb

app/controllers/v1/roles_controller.rb

app/controllers/v1/users_controller.rb

app/models/role.rb

app/models/user.rb

app/policies/activity_policy.rb

app/policies/application_policy.rb

app/policies/bookmark_policy.rb

app/policies/collection_policy.rb

app/policies/institution_policy.rb

app/policies/language_policy.rb

app/policies/learning_object_policy.rb

app/policies/license_policy.rb

app/policies/mime_type_policy.rb

app/policies/object_type_policy.rb

app/policies/publisher_policy.rb