update Readme with levels support option

README.md

@@ -95,6 +95,8 @@ Args:
 
 Options:
   -h, --help            show this help message and exit
+  -l LEVELS, --prod-id=LEVELS
+                        Processed levels
   -p PROD_ID, --prod-id=PROD_ID
                         Process only this product. All by default
   -o OUT_DIR, --out_dir=OUT_DIR