AFTER a pair of £19.50 M&S trousers went viral for their bloat-friendly waistline, Fashion Editor Abby McHale reveals how best to dress for festive (over)indulgence. From peplum tops to dresses that are both satin and flattering, we have you covered this Christmas. THE PEPLUM TOP Abby says: “Peplum tops are back, but don’t panic if…