Finally, some good news — with the slowing of the COVID-19 crisis, the world of entertainment is opening up.For starters there’s Hershey Felder, one of Chicago’s favorite producers, writers, directors and performers of famous composers, who never stopped creating or producing during the pandemic. Now he appears as Sergei Rachmaninoff in the world premiere of “Nicholas, Anna & Sergei — Live from Florence.” Streaming online through Sunday, this is the latest of Felder’s composer series which includes Beethoven, Pyotr …