Region based nnunet scripts

In this PR we detail the scripts used for the training and evaluation of the region-based nnUNet. It contains:

README.md : instructions to use the different files
convert_BIDS_to_nnunet.py : script to convert data from the BIDS format to the nnUNet format
convert_predictions_to_BIDS.py : script to convert the nnUNet predictions to the BIDS format using the conversion dictionnary
evaluate_lesion_seg_prediction.py : this script computes the metrics using anima
nnUNet_inference_analysis.ipynb : this notebook shows the performance of the nnunet with respect to its different folds
convert_BIDS_to_nnunet_with_mul_PSIR.py : this last script was added to convert BIDS to nnunet format and multiplying PSIR images by -1

This list is to be updated.

ivadomed / canproco