Description:
------------
ICU 4.4 upgraded it's resource file format. If you are using older version of ICU e.g 4.2 and try to load a newer version of resource file function returns null but there is no way of developer knowing what the hell happened. Getting some sort of error message would be most welcome otherwise you just get a WTF moment.

Test script:
---------------
<?php
error_reporting(E_ALL);
ini_set('display_errors', 1);

$resourceDir = __DIR__;
//2 files needed ar it seems ther Resoucebundle won't reload? the same file or something like that another bug?
$resFile_v1 = $resourceDir . '/en1.res';
$resFile_v2 = $resourceDir . '/en2.res';

$fileData_v1 = base64_decode('IADaJxQAAAAAAAIAUmVzQgECAAABBAAAAAAAAAAAAAALAAAgBgAAAAgAAAANAAAADQAAAAEAAAAA
AAAAZm9vAAMAAABiAGEAcgAAAAEAHAAIAAAA');

$fileData_v2 = base64_decode('IADaJxQAAAAAAAIAUmVzQgIAAAABBAAAAAAAAAAAAAAFAABQBwAAAAkAAAANAAAADQAAAAEAAAAA
AAAADQAAAGZvbwAAAGIAYQByAAAAAQAgAAEA
');

file_put_contents($resFile_v1, $fileData_v1);
$rb = new ResourceBundle('en1', $resourceDir);
var_dump($rb);
/output object(ResourceBundle)#1 (0) {
}
*/

file_put_contents($resFile_v2, $fileData_v2);
$rb = new ResourceBundle('en2', $resourceDir);
var_dump($rb);
/output object(ResourceBundle)#1 (0) {
}
*/
//no error no warning nothing

unlink($resFile_v1);
unlink($resFile_v2);