Add resource minio_s3_bucket_notification

[aminueza]

Add a new resource to manage buckets notifications.

Some rules to follow:

• add a new tag in provider.go: minio_s3_bucket_notification;

• add an object in payload.go file named as
  type S3MinioNotification struct

• create a func in check_config.go to fill up the object structure:
  func S3NotificationConfig

• check terraform example;

• check go code for AWS s3 notification;

• add a test file naming as minio_s3_notification_test.go and follow the same template for test written in resource_aws_s3_notification_test.go;

• update the documentation creating a new S3_BUCKET_NOTIFICATION.md file;

• create a .tf file with an example in examples/bucket/bucket.tf;