As many other industries around them contracted, the biotech and medical-device sectors in Massachusetts added more than 8,000 jobs over the past five years. What’s more, while life-sciences employment nationwide increased 12 percent nationally since 2000, Massachusetts’ grew more than twice as fast. The state’s edge? The Massachusetts Life Sciences Center, according to a recent Boston Foundation report. With these kinds of results, the center is one job-creating initiative lawmakers should continue to fund generously.