PRODUCT_ORDER_CREATE_INVOICE PRODUCT Endpoint
  /rpc/product/?method=PRODUCT_ORDER_CREATE_INVOICE  
  Creates an Invoice based on an Order / Delivery  
  Uses Profile Setting 432 to control the line item description: 1 = include unit cost [default], 2 = do not include unit cost  
  PARAMETERS TYPE  
  Delivery Numeric Id of the Delivery
  Id Numeric Mandatory. Id of the Order
  ItemFormat Numeric Format of the Invoice's Line Items. Default 1.
1: [OrderItem.InvoiceDescription, or if blank, Product.Title] : [OrderItem.Quantity] @ [Product.UnitPrice] per [Product.UnitTypeText]
2: [OrderItem.InvoiceDescription, or if blank, Product.Title] : [OrderItem.Quantity]
3: [Product.Title] - [OrderItem.InvoiceDescription] x [OrderItem.Quantity] @ [Product.UnitPrice] per [Product.UnitTypeText]
  SentDate Date If not passed, defaults to Today
  RETURN  
  Invoice Id of the created Invoice
  EXAMPLE
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