[purchase] Purchase orders based on incoming shipment should be done when invoices are paid, not just validated

Hello,

I have fixed the issue : Purchase orders based on incoming shipment should be done when invoices are paid, not just validated.

More details:
Task Link: https://accounts.openerp.com/web#id=7359&view_type=form&model=project.task&menu_id=3942&action=327
Pad Link: https://pad.odoo.com/p/openerp-project.task-BWF12UZ2N4
Thanks,
cod-odoo