Singapore is banking on lavish beachfronts, canopy walks, a transformed port and even water taxis to upgrade its holiday island, Sentosa, into a major tourism draw over the next two decades – but observers say the challenge will be in guaranteeing distinctiveness.On Friday, the Sentosa Development Corporation (SDC) unveiled plans to rejuvenate the 5 sq km resort and theme park island, which is located 10 minutes from the Singapore mainland by monorail and is also accessible by car or bus...