WIP BibCheck: port to pu

Work so far done is regarding a stable configuration format interface to work towards an API, using manager.py and utilizing workflows.
Neither PEP257 nor [Rope](http://rope.sourceforge.net/) (which I forgot to run on this module) have empty lines before/after docstrings. Rope's "organize imports" function in vim actually removes empty lines after module docstrings. Is this an invenio convention?