* added utf-8 markers to all .py files in plugins/filter
* added utf-8 markers to all .py files in plugins/inventory
* added utf-8 markers to all .py files in plugins/lookup
* Update targets for CI for devel branch; move some targets to stable-2.10.
* Skipping test on RHEL 8.3 (it is already skipped on RHEL 8.2).
* Linting.
* Shut 2.9/2.10 pylint complaints up.
* callback_type -> type.
* Mark authors as unknown.
* Add author field forgotten in #627.
* Fix author entries.
* Add author field forgotten in #127.
* Fix some types.