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* Add tests for python 3.6, 3.7, 3.8, 3.9, pypy
* Add tests for sqlite, mysql, mariadb, postgresql
* Fix bug that broke ``delete_content_blocks`` when using mysql on sqlalchemy 1.3
* Docs: Add db schema diagram
* Docs: Clarify how to get default data in a default (development) docker instance
* Fix implicit routing in TAXII 1.1 Inboxes
* Update jwt usage to pyjwt >= 2.0 (thanks `SanyaKapoor <https://github.com/SanyaKapoor>`_)