def send_invoice(invoice)
      response = post_xml(invoice.to_xml, {:action => 'send', :type => 'invoice'})
      InvoiceParser.parse(response, invoice)
    end
def send_invoice(invoice)
      response = post_xml(invoice.to_xml, {:action => 'send', :type => 'invoice'})
      InvoiceParser.parse(response, invoice)
    end
Sends an invoice