This script executes cake i18n extract
with all the defaults args and returns the command output.
function extractPotFiles(){
$app = ROOT . DS . APP_DIR;
$cake = $app . DS . 'Console' . DS . 'cake';
$olddir = getcwd();
chdir($app);
$descriptorspec = array(
0 => array("pipe", "r"), // stdin is a pipe that the child will read from