MIT’s 49th annual Celebration of the Life and Legacy of Dr. Martin Luther King Jr. took place Wednesday before an overflow crowd at Morss Hall and featured activist and author Angela Y. Davis as its keynote speaker. The celebration luncheon was the lead event in a week of activities honoring the civil rights leader, and its theme was: “Let us uphold the flame for fairness and justice. There’s a certain kind of fire that must not be extinguished.” In her address, Davis said, “Each year we witness ever more compelling…