code highlight correction in doc

README.md

@@ -13,7 +13,9 @@ Change the following variables for usage:
 ### Additions
 
 To replace/edit certain text in mirrored version, add following after line 15
-```sed -i 's/EXISTING-TEXT/TEXT-TO-REPLACE-IT/g' FILE```
+```
+sed -i 's/EXISTING-TEXT/TEXT-TO-REPLACE-IT/g' FILE
+```
 
 ### License