Added sitename

Sed.md

@@ -6,6 +6,12 @@ Example:
 sed -i 's/DOMAINname/'$domain'/' <path/to/filename>
 ```
 
+### SITEname: should be replaced with $sitename
+Example:
+```
+sed -i 's/SITEname/'$sitename'/' <path/to/filename>
+```
+
 ### PHPver: should be replaced with $phpver
 Example:
 ```