In a sweeping change for the nation’s largest retailer, Walmart U.S. will eliminate synthetic dyes along with 30 ingredients from its private food labels.  In-house brands Great Value, Marketside, Freshness Guaranteed and Bettergoods will undergo what is one of the largest retail brand overhauls ever and the first for a major retailer, according to the company. "Our customers have told us they want products made with simpler, more familiar ingredients and we’ve listened," said Walmart U.S. CEO John Furner.  ...