I have created this Python script that will download all your designs from Thingiverse into folder compatible with Git.
A simple list is generated and each folder contains all the files, images and description of each design.
The basic instructions are:
- Create an empty git repo
- Copy the file export_things.py to the root folder
- Edit the file to match your user, name, description… etc
- Run as “python export_things.py”
- Au revoir Thingiverse!!
Hope you find it useful, let me know if you create a repo with it! 
UPDATE: Created repository https://github.com/carlosgs/export-things
https://github.com/carlosgs/carlosgs-designs/blob/master/export_things.py
https://github.com/carlosgs/carlosgs-designs