Improve Summary and Help messages

src/command_def.ml

@@ -204,11 +204,13 @@ let run ~version ~build_info () =
   let exit_code =
     match
     group
-      ~summary:"OcLaunch program is published under CeCILL licence.\nSee \
+      ~summary:"OcLaunch program is published under CeCILL licence.\n You may \
+      run the program with 'licence' command or see \
       http://cecill.info/licences/Licence_CeCILL_V2.1-en.html (http://huit.re/TmdOFmQT) for details."
-      ~readme:(fun () -> "See http://oclaunch.tuxfamily.org for help.")
       [ ( "reset-tmp", reset) ; ("list", list) ; ("add", add) ; ("delete",
       delete) ; ("state", state) ; ("edit", edit) ; ("licence", licence) ; ("run", default) ]
+      ~readme:(fun () -> "Use '-h' flag to get help (it works both after the \
+      name of the software and with a subcommand). For further help, see http://oclaunch.tuxfamily.org for help.")
     |> run ~version ~build_info
     with
     | () -> `Exit 0