Jormungandr: avoid non pt journeys to be choosen as standard journey

That's really hard to read. Consider writing a `is_better_standard` boolean function to make it clean what you want. I suppose you want standard be the journey s.t. min(lex(not_pt, car, criteria)).

Here, if you have standard = {pt, car} and journey = {not_pt, not_car}, you'll set journey to standard, and I don't think you want that.