1. IBAN validation in member admin.
2. In the transaction overview, for every transaction an EPC-QR code for banking apps is generated and displayed. The (necessary) BIC field is automatically derived from the IBAN. This closes#63.
Both steps use the python library schwifty.
Reviewed-on: digitales/kompass#94
Reviewed-by: Christian Merten <christian@merten.dev>
Co-authored-by: marius.klein <marius.klein@alpenverein-heidelberg.de>
Co-committed-by: marius.klein <marius.klein@alpenverein-heidelberg.de>
marius.klein