Merge branch 'dev' into f-cleanup-ci

.docker/Dockerfile

.gitlab-ci.yml

.gitlab/merge_request_templates/Default.md

CHANGELOG.md

Makefile

pycaosdb.ini.template

tests/test_administration.py

tests/test_affiliation.py

tests/test_authentication.py

tests/test_creation.py

tests/test_datatype.py

tests/test_datatype_inheritance.py

tests/test_deletion.py

tests/test_empty_text_value.py

tests/test_error_stuff.py

tests/test_file.py

tests/test_importance.py

tests/test_inheritance.py

tests/test_issues_mysqlbackend.py

tests/test_issues_server.py