NEW YORK (Reuters) -- A peppy Scottish terrier known as Sadie was crowned the nation's top dog on Tuesday, winning Best in Show at the prestigious Westminster Kennel Club championship. Sadie, a jet-black four-year-old bitch formally known as Ch Roundtown Mercedes of Maryscot, displayed the ideal combination of breeding standards and confidence, beating out 2,500 entrants at the 134-year-old dog show. "She's the total package," marveled Elliot Weiss, of Eagle, Idaho, who judged the Best in Show round before a cheering, capacity crowd at Madison Square Garden. "This is the complete dog ... That's what you want a Scottie to...