Stocks rallied Monday with the Dow logging its biggest point gain in history. The S&P 500(https://www.webull.com/quote/idxsp-inx) gained $1.1 trillion Monday. But an all-day system-wide outage left Robinhood customers seething. The free stock-trading app, crashed on the worst day possible.Tuesday, as global markets rebounded after a sell-off last week and then sank again, Robinhood’s trading platform went offline, leaving many customers to watch their portfolios drop in value without being abl...