This stuff was provided by Gregory G.; it was used just once during
download and is probably irrelevant henceforth.

Gregory wrote:

  If you want to download the full covariance matrices as well, you can
  either edit and re-run get_zenodo_filelist.py (comment out the line
  starting with "if fname.startswith"), or you can ask me, and I'll send
  the full file list.

(for now, I'm happy to reference zenodo for them)