When the federal government awarded $349 billion in small business loans, Newark’s IDT Corp., whose stock is traded on the New York Stock Exchange and is worth $144 million, walked away with a maximum loan of $10 million. Six days later, the company returned the money.Not so SilverSun Technologies Inc., a company worth almost $10 million whose stock is traded on NASDAQ. The East Hanover-based company so far has kept the $3.2 million loan it received under the paycheck protection program.In all, 15 publicly traded Garden State companies received funding from the first round of small business lo…