https://bintray.
https://bintray.com/docs/api/#_get_attributes
https://bintray.
https://bintray.com/docs/api/#_delete_attributes
https://bintray.
https://bintray.com/docs/api/#_set_attributes
https://bintray.
https://bintray.com/docs/api/#_update_attributes
version attr interface