Get a list of folders [preprocessed, feature-files, model].

def get_recognizer_folders(model_folder):
    """Get a list of folders [preprocessed, feature-files, model]."""
    folders = []
    folder = model_folder
    while os.path.isdir(folder):
        folders.append(folder)
        # Get info.yml
        with open(os.path.join(folder, "info.yml")) as ymlfile:
            content = yaml.load(ymlfile)
        folder = os.path.join(get_project_root(), content['data-source'])
    return folders[::-1]