YouTube hired long-time Walt Disney Co. executive Justin Connolly to serve as its global head of media and sports, a sign of the popular video service’s growing ambitions in traditional entertainment.Connolly is joining YouTube in a new position that will put him in charge of the service’s relationships with major media companies, including those that supply programming to YouTube TV, its cable-like online subscription video service. He’ll also be in charge of the company’s growing live-sports p...