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* Moved container handling logic to policy classes.
* Better support for multiple maps and multiple clients.
* Added ``startup``, ``shutdown``, and ``update`` actions, referring to variable policy implementations.
* Added ``persistent`` flag to container configurations to differentiate during cleanup processes.
* Added methods for merging container maps and configurations.
* It is no longer required to use the wrapped client ``DockerClientWrapper``.
* More flexible logging.