[Feature] download command supports only downloaing config

[zhouzaida]

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[nok]

Good development! I just have a small hint.

The config file should be downloaded at first and after that the checkpoint file, because in general the config file is smaller than the checkpoint file. In addition we can write more elegant source code and avoid the indentation of the (if) condition:

Original source code:

    for config in configs:
        click.echo(f'processing {config}...')
        
        # download checkpoint
        if not ignore_checkpoint:
            checkpoint_urls = model_info[config]['weight']
            for checkpoint_url in checkpoint_urls.split(','):
                # ...
                checkpoints.append(filename)

        # checkpoint config
        config_paths = model_info[config]['config']
        for config_path in config_paths.split(','):
            # ...

    return checkpoints

Changed source code:

    for config in configs:
        click.echo(f'processing {config}...')

        # download config
        config_paths = model_info[config]['config']
        for config_path in config_paths.split(','):
            # ...

        if ignore_checkpoint:
            continue

        # download checkpoint
        checkpoint_urls = model_info[config]['weight']
        for checkpoint_url in checkpoint_urls.split(','):
            # ...
            checkpoints.append(filename)

    return checkpoints

@zhouzaida , what do you think?