use parent's stdios

What do you think about using the parent's stdios?

This comes in handy, e.g., when the child has colored outputs, like when using [debug](https://github.com/visionmedia/debug)

With own stdios:
![screenshot 2014-05-09 13 43 53](https://cloud.githubusercontent.com/assets/409021/2927610/46e1f826-d76f-11e3-8db1-31c98c4f99d5.png)

With parent's stidos:
![screenshot 2014-05-09 13 43 36](https://cloud.githubusercontent.com/assets/409021/2927612/4df44b64-d76f-11e3-8348-dfa85796cc24.png)