[FIX] - budget: Fixed error on manual purchase orders

Modified purchase.order.line write method that was preventing purchase order lines to change it's status to aproved
Merge pull request #48 from CLEARCORP-dev/7.0_budget

[FIX] - budget: Fixed error on manual purchase orders
[FIX] - budget: Fixed missing program line when generating invoices
Merge pull request #49 from CLEARCORP-dev/7.0_budget

[FIX] - budget: Fixed missing program line when generating invoices