Add FacebookBatchRequest factory method

Author: teldosas

src/Facebook/Facebook.php

@@ -494,6 +494,27 @@ public function sendBatchRequest(array $requests, $accessToken = null, $graphVer
         return $this->lastResponse = $this->client->sendBatchRequest($batchRequest);
     }
 
+    /**
+     * Instantiates an empty FacebookBatchRequest entity.
+     *
+     * @param  AccessToken|string|null $accessToken  The top-level access token. Requests with no access token
+     *                                               will fallback to this.
+     * @param  string|null             $graphVersion The Graph API version to use.
+     * @return FacebookBatchRequest
+     */
+    public function newBatchRequest($accessToken = null, $graphVersion = null)
+    {
+        $accessToken = $accessToken ?: $this->defaultAccessToken;
+        $graphVersion = $graphVersion ?: $this->defaultGraphVersion;
+
+        return new FacebookBatchRequest(
+            $this->app,
+            [],
+            $accessToken,
+            $graphVersion
+        );
+    }
+
     /**
      * Instantiates a new FacebookRequest entity.
      *