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.
better code style example:
```python
...
## 59 Temple Place, Suite 330, Boston, MA 02111-1307, USA.
                                          # empty line needed
"""Docstring needed."""                   # PEP257 friendly docstring
                                          # empty line needed
from argparse import ArgumentTypeError    # external imports first
                                          # empty line recommended
from .common import ALL                   # relative imports last


...
```