PHP: Slug Function

<?php

/**
 * Create a slug to use in a url
 * Dependency: php_intl (extension)
 *
 * @author Neophitus
 * @param string $text Text to transform
 * @param bool $tolower Convert or not to lowercase
 * @return string
 */
function slug($text, $tolower = true)
{
    $allowed = '~[^-,;.a-z0-9\s]~iu';

    $text = transliterator_transliterate('Any-Latin; Latin-ASCII', $text);
    if ($tolower) {
        $text = mb_strtolower($text);
    }
    $text = preg_replace($allowed, '', $text);
    $text = preg_replace('~[.,;)(\s]+~', '-', trim($text));
    $text = preg_replace('~-{2,}~', '-', $text);

    return $text;
}