added missing includes to avoid E_FATAL

git-svn-id: http://framework.zend.com/svn/framework/standard/trunk@23354 44c647ce-9c0f-0410-b52a-842ac1e357ba

tests/Zend/XmlRpc/RequestTest.php

@@ -21,6 +21,9 @@
  */
 
 require_once 'Zend/XmlRpc/Request.php';
+require_once 'Zend/XmlRpc/Value/Nil.php';
+require_once 'Zend/XmlRpc/Value/String.php';
+
 require_once 'PHPUnit/Framework/TestCase.php';
 require_once 'PHPUnit/Framework/IncompleteTestError.php';