Sends the user to a different installer page.
This issues an on-site HTTP redirect. Messages (and errors) are erased.
$path: An installer path.
function install_goto($path) {
global $base_url;
include_once DRUPAL_ROOT . '/includes/common.inc';
header('Location: ' . $base_url . '/' . $path);
header('Cache-Control: no-cache');
// Not a permanent redirect.
drupal_exit();
}