Katcp

* Address deprecation issues in Python 3.9 (PR [263](https://github.com/ska-sa/katcp-python/pull/263))

* consistent error message in py2 and py3 for error in Timestamp decode (PR [258](https://github.com/ska-sa/katcp-python/pull/258))

* Fix issues in KATCPReply `__repr__` in py3 (PR [256](https://github.com/ska-sa/katcp-python/pull/256))

* Add asyncio compatible ioloop to ioloop manager (PR [254](https://github.com/ska-sa/katcp-python/pull/254))

* Add bulk sensor sampling feature (PR [197](https://github.com/ska-sa/katcp-python/pull/197))

* Support for handling generator expressions in Discrete type (PR [237](https://github.com/ska-sa/katcp-python/pull/237))
* Fix handling of strings and bytes in `get_sensor` in testutils ([240](https://github.com/ska-sa/katcp-python/pull/240))
* Allow strings or bytes for assert_request_fails and `test_assert_request_succeeds` function arguments. (PR([242](https://github.com/ska-sa/katcp-python/pull/242))
* Handle str type correctly('easier') in `testutils.get_sensor` for python 2 and python 3 ([243](https://github.com/ska-sa/katcp-python/pull/243))
* Allow bytes and strings in `test_sensor_list` comparison of sensors ([244](https://github.com/ska-sa/katcp-python/pull/244))
* Correct handling of floats `test_sensor_list` ([245](https://github.com/ska-sa/katcp-python/pull/245))
* black formatting on certain test files. (PR [246](https://github.com/ska-sa/katcp-python/pull/246))