Oracle Corp.’s rising stock price has powered Larry Ellison close to the top of the Bloomberg Billionaires Index. - AFP/Getty Image It was close, but Elon Musk has held on to his title of world’s richest person. The Tesla Inc. TSLA Chief Executive has held that title for about 300 days. But given the meteoric rise in Oracle Corp.’s ORCL stock price on Wednesday and so far this year, Larry Ellison, the company’s co-founder, is nipping at his heels. Most Read from MarketWatch The Bloomberg Billionaires I ...