The world premiere of Avengers: Endgame was last night, the reactions are quite positive, and that’s about all we want to know until we see the movie ourselves later this week. To that end, how about a completely benign yet enjoyable piece of Endgame-related content? One for the Billy Joel fans perhaps? Ask and you shall receive! The cast of Endgame teamed up with The Tonight Show Starring Jimmy Fallon to craft a very on-brand (for Fallon, at least) version of Bill Joel’s “We Didn’t Start the Fire.” The lyrics to this version go through …