* Convert arabic numerals to roman ones in fuzzy comparison, to ensure
there is no more discrepancies between "Paris 20" and "Paris XX" for
instance. Fix #112 and improve on top of #110.
* Improve handling of opendata postal codes (no more duplicates, better
Note: You should `pip install -r requirements.txt` and rebuild the
database (`python -m flatisfy build-data --config config.json`) after
Thanks @nicofrand for building the basic blocks for this!