Adding missing permission.

Also, force auto_destroy when cleaning up s3.

README.md

@@ -18,6 +18,11 @@ Permissions required:
 * AmazonVPCFullAccess
 * AmazonEKSServicePolicy
 
+To save state, those extras are needed:
+
+* AmazonS3FullAccess
+* AmazonDynamoDBFullAccess
+
 Required policy:
 
 ```json