Celebs seem to forever be “quitting” Twitter, only to return again.Sam Smith is the latest, tweeting Tuesday, “I’m logging off for a while. Some Martinis shaken not stirred are definitely in order.”The singer has taken some heat lately because of his Oscars acceptance speech.When he and Jimmy Napes won best original song Sunday night for “Writing’s on the Wall” from the James Bond movie “Spectre,” Smith said, “I read an ...