The following example `serverless.yml` fails to deploy on localstack:

```yaml
service: "localtest"

provider:
  name: "aws"
  runtime: "nodejs10.x"

functions:
  hello:
    handler: "handler.hello"
    
resources:
  Resources:
    ApiGatewayRestApi:
      Type: "AWS::ApiGateway::RestApi"
      Properties:
        Name: "${self:provider.stage}-${self:service}"
    GatewayResponseDefault400:
      Type: "AWS::ApiGateway::GatewayResponse"
      Properties:
        RestApiId:
          Ref: "ApiGatewayRestApi"
        ResponseType: "DEFAULT_4XX"
        ResponseTemplates:
          application/json: '{"errors":[{"message":"Custom text."}]}'
    GatewayResponseUnauthorized:
      Type: "AWS::ApiGateway::GatewayResponse"
      Properties:
        RestApiId:
          Ref: "ApiGatewayRestApi"
        ResponseType: "UNAUTHORIZED"
        ResponseTemplates:
          application/json: '{"errors":[{"message":"Custom text!", "extra":"Some extra info"}]}'
    GatewayResponseDefault500:
      Type: "AWS::ApiGateway::GatewayResponse"
      Properties:
        RestApiId:
          Ref: "ApiGatewayRestApi"
        ResponseType: "DEFAULT_5XX"
        ResponseTemplates:
          application/json: '{"errors":[{"message":$context.error.messageString}]}'
    GatewayResponseIntegrationTimeout:
      Type: "AWS::ApiGateway::GatewayResponse"
      Properties:
        RestApiId:
          Ref: "ApiGatewayRestApi"
        ResponseType: "INTEGRATION_TIMEOUT"
        ResponseTemplates:
          application/json: '{"errors":[{"message":$context.error.messageString}]}'

plugins:
- "serverless-localstack"

custom:
  localstack:
    stages:
      - "local"
```

The error on the localstack end is `Exception: CloudFormation deployment for resource type ApiGateway::GatewayResponse not yet implemented`.
network = config.LAMBDA_DOCKER_NETWORK
        network_str = '--network="%s"' % network if network else ''
        docker_cmd = self._docker_cmd()
        if config.LAMBDA_REMOTE_DOCKER:
            cmd = (
                'CONTAINER_ID="$(%s create -i'
                ' %s'
                ' %s'
                ' %s'
                ' %s'  
                ' --rm'
                ' "lambci/lambda:%s" %s'
                ')";'
                '%s cp "%s/." "$CONTAINER_ID:/var/task"; '
                '%s start -ai "$CONTAINER_ID";'
            ) % (docker_cmd, entrypoint, debug_docker_java_port, env_vars_string, network_str, runtime, command,
                 docker_cmd, lambda_cwd,
                 docker_cmd)
        else:
            lambda_cwd_on_host = self.get_host_path_for_path_in_docker(lambda_cwd)
            cmd = (
                '%s run -i'
                ' %s -v "%s":/var/task'
                ' %s'
                ' %s'  
                ' --rm'
                ' "lambci/lambda:%s" %s'
            ) % (docker_cmd, entrypoint, lambda_cwd_on_host, env_vars_string, network_str, runtime, command)
        return cmd
    def get_host_path_for_path_in_docker(self, path):