One of Alex Zanardi's lessons is that anyone can have a good life if they take joy in its small things, his son Niccolò said at the funeral of the former Formula One driver and Paralympic handbike champion on Tuesday.     "You don't have to be Alex Zanardi to have a wonderful life; anyone can have a wonderful, rewarding life," said Niccolò Zanardi.     "I hope everyone, myself first of all, can find a smile in the little things, because that's where the big things are built.     "When he made