Add S3 with working example.
diff --git a/README.rst b/README.rst
index d2d36a2..0ec286e 100644
--- a/README.rst
+++ b/README.rst
@@ -30,9 +30,11 @@
       client:
         enabled: true
         target:
-          engine: s3
-          host: s3.domain.com
-          bucket: bucketname
+          engine: dup
+          url: s3+http://bucket-name/folder-name
+          auth:
+            awsaccesskeyid: awsaccesskeyid
+            awssecretaccesskey: awssecretaccesskey
 
 Backup client with webdav target