Zach Galifianakis improvised a joke in The Hangover and “regretted” it, knowing it would inevitably make it into the movie. In the age of superhero movie supremacy and blockbuster filmmakers being under almost constant pressure to go bigger and top the last, straight-up comedies don’t feel quite so prevalent at the box office anymore. The 2000s fired out lots of great ones, with efforts like Step Brothers and Superbad becoming instant, on-arrival classics. If you were somebody who went to see The Hangover in theaters in 2009, you’ll remember just how big a deal it was—a big enough deal to beco…