The modifications in this commit allows the unit tests
to run on both, pytest 6.x (nose test layout) and the new
pytest 7.x (xunit test layout). This Fixes#2072 in a
much nicer way. Thanks much to @smarlowucf
Allow to read multiple markup formats. Supported are XML
and YAML. The parsing and transformation is based on the
anymarkup module. The use of anymarkup is optional and
implemented as an on demand loading module. If a user
uses a yaml config file or a request to convert into
yaml is made without an installed anymarkup module an
exception is thrown