added default for request param in SparkPostResponse and SparkPostException

Author: avigoldman

lib/SparkPost/SparkPostException.php

@@ -21,7 +21,7 @@ class SparkPostException extends \Exception
      *
      * @param Exception $exception - the exception to be wrapped
      */
-    public function __construct(\Exception $exception, $request)
+    public function __construct(\Exception $exception, $request = null)
     {
         $this->request = $request;
 

lib/SparkPost/SparkPostPromise.php

@@ -21,7 +21,7 @@ class SparkPostPromise implements HttpPromise
      *
      * @param HttpPromise $promise
      */
-    public function __construct(HttpPromise $promise, $request)
+    public function __construct(HttpPromise $promise, $request = null)
     {
         $this->promise = $promise;
         $this->request = $request;

lib/SparkPost/SparkPostResponse.php

@@ -22,7 +22,7 @@ class SparkPostResponse implements ResponseInterface
      *
      * @param ResponseInterface $response
      */
-    public function __construct(ResponseInterface $response, $request)
+    public function __construct(ResponseInterface $response, $request = null)
     {
         $this->response = $response;
         $this->request = $request;