Proforma

1. Pro-forma should have its unique number. It needs not be the same number as the final invoice
2. The Prof-forma invoice number should be sequentially numbered
3. We should be able to cancel a proforma
4. When we generate proforma from draft invoice, we should be able to confirm it after which the Pro-forma will have a unique number
5. Once a proforma is generated, the state of the invoice changes from Draft to Proforma. We should also be able to cancel the proforma and revert back to draft
6. We should be able to generate the final invoice from Proforma (a new number or same proforma number can be used in the final invoice. I suggest we generate a new number in the same numbering format for Odoo invoices)
7. Proforma Invoice does not generate any accounting entries
8. We should be able to print and email Pro-forma invoice
9. We should be able to generate a proforma invoice directly from Sales Quotation and Sales Order
10. This module should be compatible with Odoo 11, 12, 13 and 14