Adding and deleting an invoice line item without entering values causes a failure on submittal

[kbaley]

InvoicesController is expecting numbers for Quantity and UnitAmount and if you submit without these (even if they are deleted), the request is rejected.

Solutions:

• Validation on client to ensure legitimate line items have proper data
• Line items that are added and deleted in the same session can be discarded. No need to include them in the request
• When deleting a line item with no numbers, default to 0