pretty pty colors

All of the colors. I have them.

pty == pseudo terminal fools scripts into thinking we're a terminal. So we get colors.
 
![screen shot 2013-07-14 at 10 42 02 pm](https://f.cloud.github.com/assets/112170/795837/4d10e300-ed0b-11e2-9dc7-a978d248817a.png)

Things of note:
- I hamstringed shellWrap because now everything is run in a shell
- pty only gives us merged output, no separate stderr/stdout
- Is there any reason we wouldn't want to run everything in a shell?

This is one of the features I always wished travis had. So pretty.