Merge pull request #296 from PrivateStorageio/288.cleanup-tokens-table

src/_zkapauthorizer/__init__.py

src/_zkapauthorizer/api.py

src/_zkapauthorizer/config.py

src/_zkapauthorizer/model.py

src/_zkapauthorizer/resource.py

src/_zkapauthorizer/storage_common.py

src/_zkapauthorizer/tests/strategies.py

src/_zkapauthorizer/tests/test_client_resource.py

src/_zkapauthorizer/tests/test_model.py

src/_zkapauthorizer/tests/test_plugin.py

src/_zkapauthorizer/tests/test_storage_client.py

src/twisted/plugins/zkapauthorizer.py