Allow setting super user in stanza config

ReadMe.md

@@ -34,16 +34,23 @@ Example file is `stanza.sample.cfg`
 
 This files holds the stanzas to backup
 
-`stanza:repo number:path to config file`
+`stanza:repo number:path to config file:super user`
 
 If the stanza has several repo settings as in "repo1-...", "repo2-..." then the repo to target can be listed in here by ":repo number"
 
 The third optional parameter is a config file path
 
+The forth optional parameter is the super user to use
+
+If parameters are not used but laters are, the empties need to be set with just the ":"
+
+`stanza::/conifg`
+
 ```ini
 [stanzas]
 stanza_a
 stanza_b:1
 stanza_b:2
 stanza_c::/etc/to/config
+stanza_d:::super user
 ```