update readme

README.md

@@ -23,6 +23,7 @@ For more information about Turtl, please got to www.turtl.it
   Download the script turtl_deb and run it localy.
   ```
     wget https://github.com/adelolmo/turtl-debian/blob/master/turtl_deb
-    /bin/sh turtl_deb
+    /bin/sh turtl_deb 64|32 [versiom]
   ```
-  This will create the debian package under /tmp/turtldeb
+  The first parameter is the system architecture, it must be 32 or 64. The second parameter is the version of Turtl, if it's not given it will use the latest version available in https://turtl.it
+  The debian package will be created under /tmp/turtldeb