Key TakeawaysBoth of the big retail companies to report third-quarter results Tuesday  morning lifted their full-year outlooks ahead of the busy holiday selling season.Walmart issued a third upgrade to its outlook since February, offering up optimism about net-profit growth. Lowe's said same-store sales were seen falling less than previously expected. Several other retailers are set to report results and, potentially, update their outlooks later this week. Some big retailers are feeling better about the en ...