List of Projects using Boxoban-Levels

Hi,

first of all, thanks for sharing your generated levels with us.
I just integrated your levels into the OpenAi [gym-sokoban](https://github.com/mpSchrader/gym-sokoban) environment and [referenced your work](https://github.com/mpSchrader/gym-sokoban/blob/master/docs/variations/Boxoban.md). As I expect this not to be the only project using your generated levels, it would be great to have a list of projects in your readme to list projects using this repository.

If you like the idea, I could add a section to the readme.

Best,
Max

Review the repository README and the linked gym-sokoban Boxoban.md page to identify projects using these levels. Add a README section listing confirmed users of the repository, including gym-sokoban, and ensure the links and descriptions are accurate.

Written by the indexing model from the issue text.