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* Added the ``experiment.SubExperiment`` class which implements experiment inheritance! This class now
allows to refer to a different experiment module to run as parent experiment, but with parameter
modifications.
* Added a hook system to experiments, which allows for parent experiment modules to define certain points
at which custom code from child experiments may be injected.
* changed the datetime format in ``HISTORY.rst`` to the only sane option
* Fixed a minor windows compatibility problem with the automatic pathing determining for experiments.
* Added the module ``pycomex.testing`` to contain all of the utility functions and classes which are needed
to facilitate the unittests such as the ``ExperimentIsolation`` context manager.
* Refactored most unittests to use ``pytest`` instead of ``unittest``
* Fixed a bunch of unittests that were not updated for the new API
* Fixed a rather serious bug in ``testing.ExperimentIsolation`` which left permanent modifications in
in the globals dict and thus introduced side-effects in between different unittests.
**INTERFACE CHANGES**
* changed functionality and signature of ``experiment.run_experiment``. Previously this function executed
an existing experiment module by using ``subprocessing.run`` and returned the completed process instance.
Now, this works by using ``experiment.SubExperiment`` and the function actually returns an experiment
instance.
* Do to the change above, the same now applies to ``experiment.run_example``.