Megyn Kelly is ready to get back on TV. Page Six has exclusively learned that Kelly will officially start at NBC next month. “She will start in May, and her Sunday show will premiere in June,” a network insider told us. Kelly had been expected to start in July after her Fox contract expired, but she was just released from her Fox deal two weeks ago. She will join Kate Snow as part of NBC News’ Sunday night programming. NBC News vet and former “Dateline” executive producer David Corvo will executive produce Kelly’s Sunday show with another longtime NBC producer,...