Set TransactionType to recurring when cvn not available.

Cvn is required for an onsite purchase. It is not required when processing a recurring payment.
It seems reasonable to assume that if not passed, and we are working with a DirectPayment with
a token then it is a recurring payment.

Setting to MOTO would have the same effect. The practical difference between Recurring & MOTO is not clear
and there is not an obvious Omnipay standard to follow so sticking with this assumption for
now

src/Message/RapidDirectPurchaseRequest.php

@@ -82,6 +82,10 @@ public function getData()
         $data['Payment']['CurrencyCode'] = $this->getCurrency();
         $data['Payment']['InvoiceReference'] = $this->getInvoiceReference();
 
+        if (empty($data['Customer']['CardDetails']['CVN']) && $this->getCardReference()) {
+            $data['TransactionType'] = 'Recurring';
+        }
+
         if ($this->getCardReference()) {
             $data['Method'] = 'TokenPayment';
         } else {