User contributed addons

Hi,

First of all thank you for this awesome project.
I have created a stringifier for integrating [pudb + pytorch](https://github.com/georgepar/pudb-torch) to debug ML code, and
I am wondering if there is a contrib folder / side-project for user contributed themes / stringifiers.

I would find it very interesting if such a platform was created to allow users to share domain specific customizations.