BOSSES HAVE always kept tabs on their workers. After all, part of any manager’s job is to ensure that underlings are earning their keep, not shirking and definitely not pilfering. Workplaces have long been monitored, by inspectors, CCTV cameras and more recently all manner of sensors, to check how many widgets individual workers are assembling or whether anyone is dipping too liberally into the petty-cash box. In the past few years,…