Amazon Corp. is looking for a place to put a second headquarters, and the town of Scarborough is getting into the race. The town plans to submit the Scarborough Downs racetrack site as a contender for the Seattle-based online retail giant’s new headquarters facility, which would eventually employ up to 50,000 people. A town official acknowledged that even with the property’s owners on board, Scarborough Downs is an extreme long shot. “Other (cities and towns vying for the headquarters) have coordinated with state governments on tax incentives,” said Scarborough Town Manager Thomas Hall.