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`.
sqs_client = aws_stack.connect_to_service('sqs')
    queues = sqs_client.list_queues()
    url = name if '://' in name else aws_stack.get_sqs_queue_url(name)
    for queue_url in queues['QueueUrls']:
        if queue_url == url:
            return True
def topic_exists(name):
    sns_client = aws_stack.connect_to_service('sns')
    topics = sns_client.list_topics()
    for topic in topics['Topics']:
        topic_arn = topic['TopicArn']
        if topic_arn.endswith(':%s' % name):
            return topic_arn
def queue_url_exists(queue_url):
    sqs_client = aws_stack.connect_to_service('sqs')
    queues = sqs_client.list_queues()
    return queue_url in queues['QueueUrls']
def stream_exists(name):
    kinesis_client = aws_stack.connect_to_service('kinesis')
    streams = kinesis_client.list_streams()
    return name in streams['StreamNames']
def get_stack_details(stack_name):
    cloudformation = aws_stack.connect_to_service('cloudformation')
    stacks = cloudformation.describe_stacks(StackName=stack_name)
    for stack in stacks['Stacks']:
        if stack['StackName'] == stack_name:
            return stack
def describe_stack_resource(stack_name, resource_logical_id):