message: vector: Honor fixed flag.
diff: @@ -17,10 +17,10 @@ namespace std
  if (first)
  {
  first = false;
  - elle::fprintf(out, "%s", elt);
  + elle::fprintf(out, is_fixed(out) ? "%f" : "%s", elt);
  }
  else
  - elle::fprintf(out, ", %s", elt);
  + elle::fprintf(out, is_fixed(out) ? ", %f" : ", %s", elt);
  }
  elle::fprintf(out, "]");
  return out;
  