(Reuters) - British home furnishings retailer Dunelm Group Plc on Thursday boosted its expectations for full-year profit, helped by stronger margins and the smooth transition of customers to its new website.Dunelm said gross margins benefited from better sell through, a measure of direct sales made by a retailer, and gains from sourcing, despite issuing a warning on weakening profit margins in October.The company also said it did not see any hurdles in its performance while transferring..