In [this PR](https://github.com/localstack/localstack/pull/1200/files) we introduced a new way of starting S3 in a separate process.

In the meantime, the service startup has been significantly reworked, and it seems that we can integrate the S3 starter into the [`multiserver.py`](https://github.com/localstack/localstack/blob/master/localstack/utils/server/multiserver.py) based loading approach that loads multiple APIs in a single process, for performance reasons. We should look into that.
try:
            result = parse_output_orig(output_logical_id, output_json, resources_map)
        except KeyError:
            result = Output()
            result.key = output_logical_id
            result.value = None
            result.description = output_json.get('Description')
        
        if not hasattr(result, 'export_name'):
            result.export_name = output_json.get('Export', {}).get('Name')
        return result
    parse_output_orig = parsing.parse_output
    parsing.parse_output = parse_output
    
    if '<ExportName>' not in responses.DESCRIBE_STACKS_TEMPLATE:
        find = '</OutputValue>'
        replace = """</OutputValue>
        {% if output.export_name %}
        <ExportName>{{ output.export_name }}</ExportName>
        {% endif %}
        """
        responses.DESCRIBE_STACKS_TEMPLATE = responses.DESCRIBE_STACKS_TEMPLATE.replace(find, replace)
    
    def make_cf_update_stack(cf_backend):