Italian translation

Hi Daniel, thank you very much for your cheat sheet, it was really useful to me to start using git flow :smile:
 
I wrote an italian translation (```index.it_IT.html```), I hope it will be useful for italian speaking people. I also added a link to this translation into each other page.

Moreover I added some little CSS modification to fix minor problem.

Handle long list of translations:
![screen shot 2014-04-20 at 09 36 48](https://cloud.githubusercontent.com/assets/223858/2750238/bdbe75b0-c85f-11e3-9ce9-266e19818adb.png)
![screen shot 2014-04-20 at 09 36 57](https://cloud.githubusercontent.com/assets/223858/2750239/c20626ea-c85f-11e3-967d-d5a670389b03.png)

Wrap long url into code boxes:
![screen shot 2014-04-20 at 09 42 01](https://cloud.githubusercontent.com/assets/223858/2750240/d736c84e-c85f-11e3-8bfc-d4bb061dfe09.png)
![screen shot 2014-04-20 at 09 41 26](https://cloud.githubusercontent.com/assets/223858/2750241/d9ad7776-c85f-11e3-8167-eb121811af8c.png)

Feel free to contact me for any question.
Have a nice weekend
Andrea