COLUMBIA — Feuding in the Republican presidential primary kicked up a notch Wednesday when Sen. Ted Cruz responded to a cease-and-desist request from Donald Trump’s camp asking him to stop airing a TV ad with a blunt call of “file the lawsuit.†Cruz told reporters the letter accused his campaign of misleading the public in a commercial that includes older footage of Trump saying he is “very pro-choice.†“The letter said this attack ad, as they called it, is not only completely disingenuous but replete with lies, false defamatory and destructive statements and downright fabrications,†Cruz said during a...