v1.7.0

• added xRFM (D, HPO)
• added new 'tabarena-new' search space for RealMLP-HPO, including per-fold ensembling (more expensive)
  and tuning two more categorical hyperparameters
  (with better results)
• reduced RealMLP pickle size by not storing the dataset (#33)
• fixed gradient clipping for TabM
  (it did nothing previously, see #34).
  To ensure backward compatibility, it is set to None in the HPO search spaces now
  (it was already None in the default parameters).
• removed debug print in TabM training loop