* New feature: the parameter `system_support` allows you to state the level of compatibility between your code and different Operating System groups. This is purposefully done on a very high level: valid inputs are only 'Linux', 'MacOS', and 'Windows' and not specific versions and distributions. The dictionary allows three keys with a set as value each:
* `full`: The set of operating systems that are tested on production level.
* `partial`: The set of systems that should work, but are not as rigorously tested as those with full support. A system running found here logs a warning.
* `incompatible`: The set of systems of which you know they will fail to run the code properly. If an OS in this set tries to run the code, this will yield a `RuntimeError` exception.
* Tests now also run with the third beta version of the upcoming Python 3.10.
* Although the code should be completely platform independent, tests are now also run on MacOS and Windows.