By Jon Healey, Los Angeles Times (TNS) “I am not a crook.” “Mistakes were made.” “I did not have sexual relations with that woman.” The lexicon of presidential denials and non-denial denials of impropriety and illegality is replete with memorable one-liners. And on Wednesday, President Donald Trump offered a new one: “I don’t do cover-ups.” The day began with House Democrats meeting to discuss what