This will include the normal Python tests also
in pymod, hence aligning the test base for pymod
and pya.
This feature requires the pya compatibility module.
* Added unit test for this
* Provided an option for easier debugging such issues:
Setting env var KLAYOUT_VERBOSITY will enable debug levels on Python
modules (and all other binaries). Plugin loading issues can
be debugged by setting KLAYOUT_VERBOSITY=21.