Updated `uploadPreFlight` method to have option for custom name

Author: Cerlin

README.md

@@ -59,8 +59,8 @@ So far this SDK has only machine to machine authentication mechanism and the fol
 
 2. Methods available in `$file_service`
 
-        1. uploadPreFlight($file_path = "", $folder_id = 0);
-        2. upload($file_path = "", $folder_id = 0, $filename = null); // If file name is null, filename will be derived from actual file name.
+        1. uploadPreFlight($file_path = "", $folder_id = 0, $filename = null); // If filename is null, file name will be derived from actual file name.
+        2. upload($file_path = "", $folder_id = 0, $filename = null); // If filename is null, file name will be derived from actual file name.
         3. getEmbedUrl($file_id)
         4. delete($file_id)
         5. destroyTrashedFile($file_id)

src/Box/Services/Files/FileService.php

@@ -28,23 +28,24 @@ public function __construct(AppAuth $app_auth)
     /**
      * @param $file_path string
      * @param $folder_id integer
+     * @param $filename string
      * @return \GuzzleHttp\Psr7\Response
      */
-    public function uploadPreFlight($file_path = "", $folder_id = 0)
+    public function uploadPreFlight($file_path = "", $folder_id = 0, $filename = null)
     {
         Assert::integerish($folder_id, "The folder id must be an integer. Got: %s");
 
         $this->readFile($file_path);
 
-        $file_name = basename($file_path);
+        $filename = ((!is_null($filename)) ? $filename : basename($file_path));
 
         // Throws exception on 4XX response code
         return $this->guzzle_client->request(
             'OPTIONS',
             BAP::FILE_UPLOAD_PREFLIGHT,
             [
                 "json" => [
-                    "name" => $file_name,
+                    "name" => $filename,
                     "parent" => [
                         "id" => (string)$folder_id
                     ],