History stack in Dreamweaver?

A number of my students work in Dreamweaver CS6, and one of them accidently deleted a chunk of their php code last term during the final week, causing a lot of distress, obviously.

Which brings me to my question: in Netbeans there is a revision/history stack that automatically keeps track of all your changes to a particular file, and you can compare versions. In the above case that would have saved the student a lot of time and anxiety.

Does anyone know if there is an extension available that offers similar functionality in Dreamweaver? I looked a bit on google, but perhaps I am using the wrong search terms.

Here's a screen shot of aforementioned functionality: