Fix EZP-21410: object name limit does not support multibyte charset

Trimming has been changed to use a preg_replace as found here:
http://stackoverflow.com/questions/4166896/trim-unicode-whitespace-in-php-5-2
Merge pull request #715 from ezsystems/EZP-21410

Fix EZP-21410: object name limit does not support multibyte charset