Using special character & in user password, causes broken config.php

[grische]

When providing a password like vnRy4gYZ#KG4J45xRjH%Z&%F8W@Ca7zf during the install.sh questions, it will cause the config.php to look like this:

<?php
        $host = 'localhost';
        $port = '3306';
        $db   = 'openvpn-admin';
        $user = 'user';
        $pass = 'vnRy4gYZ#KG4J45xRjH%Z$pass = '';%F8W@Ca7zf';
?>