Datto, which provides outsourced information technology services to clients, began trading on the New York Stock Exchange as ‘MSP’ Wednesday morning. It priced its initial public offering at $27, raising $594 million. The stock opened 19% higher at $32, although it fell back to $28.30 later in the day, giving it a market cap of $4.5 billion. The firm intends to use its IPO proceeds to help pay...