new book makes it official: We are in the golden age of the celebrity memoir.“The Meaning of Mariah” — published Tuesday and already a critically acclaimed best seller — follows three recent, blockbuster confessionals by female superstars: “Inside Out,” by Demi Moore, “Open Book,” by Jessica Simpson, and Michelle Obama’s “Becoming.”All four women have broken barriers. Carey holds multiple Guinness World Records, including the most No.