README.md in embulk-output-redshift-0.8.5 vs README.md in embulk-output-redshift-0.8.6

@@ -72,9 +72,11 @@
 
 - **iam_user_name**: IAM user name for uploading temporary files to S3. The user should have permissions of `s3:GetObject`, `s3:PutObject`, `s3:DeleteObject`, `s3:ListBucket` and `sts:GetFederationToken`. And furthermore, the user should have permission of `s3:GetBucketLocation` if Redshift region and S3 bucket region are different. (string, default: "", but we strongly recommend that you use IAM user for security reasons. see below.)
 - **s3_bucket**: S3 bucket name for temporary files
 - **s3_key_prefix**: S3 key prefix for temporary files (string, default: "")
 - **delete_s3_temp_file**: whether to delete temporary files uploaded on S3 (boolean, default: true)
+- **copy_iam_role_name**: IAM Role for COPY credential(https://docs.aws.amazon.com/redshift/latest/dg/copy-usage_notes-access-permissions.html), if this is set, IAM Role is used instead of aws access key and aws secret access key(string, optional)
+- **copy_aws_account_id**: IAM Role's account ID for multi account COPY. If this is set, the ID is used instead of authenticated user's account ID. This is enabled only if copy_iam_role_name is set.(string, optional)
 - **options**: extra connection properties (hash, default: {})
 - **retry_limit**: max retry count for database operations (integer, default: 12). When intermediate table to create already created by another process, this plugin will retry with another table name to avoid collision.
 - **retry_wait**: initial retry wait time in milliseconds (integer, default: 1000 (1 second))
 - **max_retry_wait**: upper limit of retry wait, which will be doubled at every retry (integer, default: 1800000 (30 minutes))
 - **mode**: "insert", "insert_direct", "truncate_insert", "replace" or "merge". See below. (string, required)