Add files and commands to archive
        Use InsightsSpec.get_output() to get data

def add_to_archive(self, spec):
        '''
        Add files and commands to archive
        Use InsightsSpec.get_output() to get data
        '''
        if isinstance(spec, InsightsCommand):
            archive_path = os.path.join(self.cmd_dir, spec.archive_path.lstrip('/'))
        if isinstance(spec, InsightsFile):
            archive_path = self.get_full_archive_path(spec.archive_path.lstrip('/'))
        output = spec.get_output()
        if output:
            write_data_to_file(output, archive_path)