Adds a dash "-" between the name of the payment term and the
name of the bank on the invoice, in case the payment term is a RiBa.

Previously, the name of the payment term and the bank were
contiguous, without even a space in between.

Cannot confirm an invoice with C/O (RiBa) payment if the bank has not
been set on the invoice.

If creating an invoice with C/O for a contact without a bank,
fall back on the commercial partner's bank.