NWUKFS-390 (VAT9) Calculate ouput Vat on income tx * add custom dd definitions for ar documents
* Implement custom ServiceBillingDocument that generates vat pending gl lines
* Redefine ojb for service billing
NWUKFS-436 Service Billing Vat Flag
* Introduce service billing document
* Modify accounting lines ojb to expose vatable
* liquibase script to add new vatable column on accounting_lines