Shoppers are still flocking to Walmart . The company raised its full-year earnings and sales outlook Thursday, heading into the crucial holiday shopping season. Walmart also offered fresh signs that it is shedding its original identity as a strictly down-market brick-and-mortar operation by growing its e-commerce business and increasing its market share of higher-income households. The biggest retailer and grocer in the United States reported that same-store sales for Walmart U.S. rose 4.5% in