Add parameter feature

```
$callback = function($p1, $p2, $p3 = nul) {

};
$fork1 = $process->fork($callback, null, null, [$p1, $p2, $p3]);
$fork2 = $process->fork($callback, null, null, [$p1, $p2]);

$fork2 = $process->fork($callback, null, null, [$p1]); // This will not work without error message.
```