Merge branch 'tests-refactor' into 'master'

tests-extra/tests/catalog/basic/test.py

tests-extra/tests/catalog/gen_groups/test.py

tests-extra/tests/catalog/generate/test.py

tests-extra/tests/catalog/groups/test.py

tests-extra/tests/catalog/kill/test.py

tests-extra/tests/catalog/many_zones/test.py

tests-extra/tests/catalog/multi/test.py

tests-extra/tests/catalog/rapid_updates/test.py

tests-extra/tests/ixfr/bind_knot/test.py

tests-extra/tests/ixfr/knot_bind/test.py

tests-extra/tests/ixfr/knot_knot/test.py

tests-extra/tests/modules/dnsproxy/test.py

tests-extra/tools/dnstest/config.py

tests-extra/tools/dnstest/server.py