The Avengers”: The pure enjoyment offered by the Marvel mega-event showed that sometimes it’s not great art, but great commerce that expresses the magic of the movies. The summer popcorn hit not only broke the box-office bank, it lived up to expectations and healed the wounds from the 2003 “Hulk” movie by introducing a new big green guy, Mark Ruffalo, with just the right tone of wry empathy….
