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- Drop support for Python 2.7, 3.3, 3.4 and 3.5
- Remove both the aiohttp and the tornado transport class from Zeep. These
can be moved to their own Python package if anyone is interested.
- Add `zeep.transports.AsyncTransport` which is based on `httpx`. Note that
loading wsdl files is still a sync process but operations can be executed via
async.
- Start adding more typehints to the package