Quentin Tarantino sure likes to play with history. He did this, most jarringly, in 2009’s Inglorious Basterds. Believe it or not, Hitler was not roasted in a movie theater and peppered with bullets by avenging Jews. This year, when Once Upon a Time… In Hollywood premiered, fans got to wondering if Tarantino would be telling the real story of the Manson murders, or some fantasy version. If you’ve seen the movie, you know that the historical record was altered just a little. However, careful attention to detail was a priority for the film, its researchers working hard to …