sasa -reg: generate an action in state.ml (as required by the API)

lib/sasacore/genRegister.ml

@@ -71,6 +71,7 @@ let (f: string list -> string * string * string -> unit) =
 let to_string _ = \"define_me\"
 let of_string = None
 let copy x = x
+let actions = [\"a\"]
 ";
       flush oc;
       close_out oc;