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- decoupled threaded networking from ws-discovery implementation
- refactored app-level discovery & publishing code into their own modules
- refactored message construction, serialization & deserialization
- added new ``wspublish`` command-line client to publish a service
- added unicast discovery support to ``wsdiscover``command-line client
- collected all namespaces in one module
- improved README example
- good documentation in reStructuredText with Sphinx
- removed Python 2 support code