Reuters: China hit back on Saturday at U.S. claims it was shirking in the fight against climate change, likening the criticisms to a mythic pig preening itself. Frustration between the world’s two top carbon polluters overshadowed week-long U.N. talks seeking progress on the shape of a new climate pact, with negotiators making some progress on financing but failing to dispel fears the process could end in deadlock. Su Wei, a senior Chinese climate change negotiator, swiped at comments …