Elon Musk’s reign as the world’s richest man may soon be challenged — and the contender is none other than Oracle co-founder Larry Ellison. The 81-year-old billionaire saw his fortune swell by a staggering $70 billion in just one day, after Oracle Corp. delivered an aggressive outlook for its cloud business that sent its shares skyrocketing.Ellison, who serves as chairman and chief technology officer of Oracle, has the bulk of his net worth tied up in the database software company. His net worth has now sur ...