new module: ctree

[elena-buscaroli]

Is there an existing module for this?

• [x] I have searched for the existing module

Is there an open PR for this?

• [x] I have searched for existing PRs

Is there an open issue for this?

• [x] I have searched for existing issues

Further Information

R package: https://github.com/caravagnalab/ctree

Are you going to work on this?

• [x] If I'm planning to work on this module, I added myself to the Assignees to facilitate tracking who is working on the module