EPC forbide Ccy in DbtrAcct

issue4309
review7681002
Set correctly sequence type on payment

If the mandate is set on the payment before the process, the sequence type is
not set. Also the sequence type should be cleared when copying.

issue4322
review14641002
Add support for many payments per end_to_end_id in CAMT054

The unique link between end_to_end_id and payment is not garantee by the
design. So the handler should work in case of customization.

issue4307
review9831002