Support Versioned and DeltaSyncConfig

[yyoshiki41]

AppSync currently supports versioning on DynamoDB data sources.
https://docs.aws.amazon.com/appsync/latest/devguide/conflict-detection-and-sync.html

I want to configure this options.

Example of CloudFormation template is below.
we need Versioned and DeltaSyncConfig sections.

  DynamoDBPostsTableDatasource:
    Type: AWS::AppSync::DataSource
    Properties:
      Type: AMAZON_DYNAMODB
      Name: posts
      ApiId:
        Fn::GetAtt:
        - DeltaSyncApi
        - ApiId
      ServiceRoleArn: !GetAtt AppSyncTutorialAmazonDynamoDBRole.Arn
      DynamoDBConfig:
        TableName:
          Ref: DynamoDBTableDeltaSyncPostsTable
        AwsRegion:
          Ref: AWS::Region
        UseCallerCredentials: FALSE
        Versioned: TRUE
        DeltaSyncConfig:
          DeltaSyncTableName:
            Ref: DynamoDBTableDeltaSyncDeltaTable
          DeltaSyncTableTTL: 60
          BaseTableTTL: 0

thanks.

[bboure]

Thank you @yyoshiki41
If you want to collaborate and open a PR to help with this, you are very welcome.

Useful resources:
https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/aws-properties-appsync-datasource-dynamodbconfig.html#cfn-appsync-datasource-dynamodbconfig-versioned

[yyoshiki41]

@bboure

Thanks for your info!
I create a new pr to resolve this issue.
#313