fix wp_title() so it behaves just like the standard wp themes

this should close my own issue (https://github.com/320press/wordpress-bootstrap/issues/169) while not interfering with other plug-ins or stuff that expects wp_title() to be where it is. there's a similar issue on your wordpress foundation theme (https://github.com/320press/wordpress-foundation/issues/28) that would also be fixed by this patch to functions.php.

thanks for the great work!