Merge branch 'dev' into 'f-mypy'

unittests/test_error_handling.py

unittests/test_exception.py

unittests/test_file.py

unittests/test_issues.py

unittests/test_message.py

unittests/test_plantuml.py

unittests/test_property.py

unittests/test_query.py

unittests/test_record.py

unittests/test_record_type.py

unittests/test_schema.py

unittests/test_server_side_scripting.py

unittests/test_state.py

unittests/test_utils.py

unittests/test_versioning.py

unittests/test_yamlapi.py