## Issue description
When creating a CloudFormation stack, the `CreationDate` is always `2011-05-23T15:47:44Z`

## Steps to reproduce
1. Prepare a CloudFormation file, for example
```yml
AWSTemplateFormatVersion: 2010-09-09
Description: My Stack
Resources:
  LambdaCodeBucket:
    Type: AWS::S3::Bucket
    Properties:
      BucketName: my-bucket
```
2. Create a new stack based on this file, I used the command:
```bash
awslocal cloudformation create-stack --stack-name gch --template-body file://stack.yml
```
3. List all the created stacks and confirm the `CreationDate` is not a present date
```
awslocal cloudformation list-stacks
```
```
{
    "StackSummaries": [
        {
            "StackId": "arn:aws:cloudformation:us-east-1:000000000000:stack/stack/27187f13-a645-40a0-8788-62d502358216",
            "StackName": "stack",
            "TemplateDescription": "My Stack",
            "CreationTime": "2011-05-23T15:47:44Z",
            "StackStatus": "CREATE_COMPLETE"
        }
    ]
}
```
response = Response()
    response._content = """<{op_name}Response xmlns="{xmlns}">
      <{op_name}Result>
        {content}
      </{op_name}Result>
      <ResponseMetadata><RequestId>{uid}</RequestId></ResponseMetadata>
    </{op_name}Response>""".format(xmlns=XMLNS_CLOUDFORMATION,
        op_name=operation_name, uid=uuid.uuid4(), content=content)
    response.status_code = code
    return response
def validate_template(req_data):
    LOG.debug('Validate CloudFormation template: %s' % req_data)
    
    response_content = """
        <Capabilities></Capabilities>
        <CapabilitiesReason></CapabilitiesReason>
        <DeclaredTransforms></DeclaredTransforms>
        <Description></Description>
        <Parameters>
        </Parameters>
    """
    try:
        template_body = get_template_body(req_data)
        template_deployer.template_to_json(template_body)
        response = make_response('ValidateTemplate', response_content)
        return response
    except Exception as err:
        response = error_response('Template Validation Error: %s' % err)
        return response
def transform_template(req_data):