Feature Request - Static Output name

[Crain-32]

In randomizer.py the randomized iso is saved using the following.

    if self.export_disc_to_folder:
      output_folder_path = os.path.join(self.randomized_output_folder, "WW Random %s" % self.seed)
      yield from self.gcm.export_disc_to_folder_with_changed_files(output_folder_path)
    else:
      output_file_path = os.path.join(self.randomized_output_folder, "WW Random %s.iso" % self.seed)
      yield from self.gcm.export_disc_to_iso_with_changed_files(output_file_path)

Being able to specify a specific filename and save/overwrite an existing ISO would be great for people who use small USB/SD cards for Console, and don't want to keep the old ISOs around.