Check if the current env can be used to restore files.

def check_for_usable_restore_env(self):
        """Check if the current env can be used to restore files."""
        self.check_for_usable_environment()

        if not os.path.isdir(self.mackup_folder):
            utils.error("Unable to find the Mackup folder: {}\n"
                        "You might want to back up some files or get your"
                        " storage directory synced first."
                        .format(self.mackup_folder))