Add fabric output to event text

- don't display the stdout if not needed
- handle multiple commands output display
- add an example

Fixes #94

Events generated:
![screen shot 2014-05-27 at 6 20 55 pm](https://cloud.githubusercontent.com/assets/1532259/3098665/42e6790c-e5ef-11e3-82b7-9305c1e2a9ae.png)

![screen shot 2014-05-27 at 6 20 34 pm](https://cloud.githubusercontent.com/assets/1532259/3098667/445b4a2e-e5ef-11e3-9914-b6bbdc07ada2.png)

![screen shot 2014-05-27 at 6 28 19 pm](https://cloud.githubusercontent.com/assets/1532259/3098671/47035c26-e5ef-11e3-9fb8-3843d1148b91.png)

![screen shot 2014-05-27 at 6 27 07 pm](https://cloud.githubusercontent.com/assets/1532259/3098668/45bba3aa-e5ef-11e3-845e-068dd46aecd2.png)
This last screenshot shows that the text collapses if it's too long, it's not the actual result of the example command.