The basic idea is to store the variable and group information in JSON files and then export it to either JSON or XML. I use XML, since Qlikview (which I am using) doesn't have native JSON import functionality.
There is not much documentation (see the github repository readme), but it is pretty straightforward and you can contact me with any questions at firstname.lastname@example.org.
When you install, there is some sample data so you can see what the end result is before you spend a bunch of time entering your own data.
Here are a couple of screenshots of the application: