* Add a custom journal items view based on an analysis of several production system
* Display credit only if account_banking_sepa_credit_transfer is installed
* Display debit only if account_banking_sepa_direct_debit is installed
* Create a new journal entry ref field which will contain the number of the related invoice if it exist and if the state of the releted move is draft.
otherwise, it will contain the name of the related journal entry.
This fixes#93.
- filter invoices that are already in draft and open payment orders.
- use residual amount to care for partial reconciliations and align with official 8.0
