* Fix page redirection on loan delete.
* Add dedicated status for loan with started payment (show if payment is
started on loan card).
* Add fk_payment_loan property for loan_schedule and add link to loan payment
on shedule page for paid line.
* Make it not possible to use schedule if start loan payment without it (else
values in schedule can't be good).
* If modify capital in payment with schedule set, automatically updates it
with the new value.
* Can't modify interest in payment if schedule is used (causes the
inconsistency for value in schedule).
* User right verification on schedule page.