Allow 'source' parameter when creating a customer

src/Message/CreateCustomerRequest.php

@@ -104,14 +104,24 @@ public function setEmail($value)
         return $this->setParameter('email', $value);
     }
 
+    public function getSource()
+    {
+        return $this->getParameter('source');
+    }
+
+    public function setSource($value)
+    {
+        $this->setParameter('source', $value);
+    }
+
     public function getData()
     {
         $data = array();
         $data['description'] = $this->getDescription();
 
         if ($this->getToken()) {
             $data['card'] = $this->getToken();
-            
+
             if ($this->getEmail()) {
                 $data['email'] = $this->getEmail();
             }
@@ -126,6 +136,10 @@ public function getData()
             $data['metadata'] = $this->getMetadata();
         }
 
+        if ($this->getSource()) {
+            $data['source'] = $this->getSource();
+        }
+
         return $data;
     }