Apply patch from docusign#41

Author: Ben Burleson

src/ObjectSerializer.php

@@ -79,7 +79,7 @@ public static function sanitizeForSerialization($data)
      *
      * @return string the sanitized filename
      */
-    public function sanitizeFilename($filename)
+    public static function sanitizeFilename($filename)
     {
         if (preg_match("/.*[\/\\\\](.*)$/", $filename, $match)) {
             return $match[1];
@@ -251,14 +251,17 @@ public static function deserialize($data, $class, $httpHeaders = null)
             } else {
                 return null;
             }
-        } elseif (in_array($class, ['DateTime', 'bool', 'boolean', 'byte', 'double', 'float', 'int', 'integer', 'mixed', 'number', 'object', 'string', 'void'], true)) {
+        } elseif ($class === 'DateTime' || in_array(strtolower($class), ['bool', 'boolean', 'byte', 'double', 'float', 'int', 'integer', 'mixed', 'number', 'object', 'string', 'void'], true)) {
+            if ($class !== 'DateTime') {
+                $class = strtolower($class);
+            }
             settype($data, $class);
             return $data;
         } elseif ($class === '\SplFileObject') {
             // determine file name
             if (array_key_exists('Content-Disposition', $httpHeaders) &&
                 preg_match('/inline; filename=[\'"]?([^\'"\s]+)[\'"]?$/i', $httpHeaders['Content-Disposition'], $match)) {
-                $filename = Configuration::getDefaultConfiguration()->getTempFolderPath() . sanitizeFilename($match[1]);
+                $filename = Configuration::getDefaultConfiguration()->getTempFolderPath() . self::sanitizeFilename($match[1]);
             } else {
                 $filename = tempnam(Configuration::getDefaultConfiguration()->getTempFolderPath(), '');
             }