Late-night disco partying. Elbow-to-elbow seating in movie theaters. Mask-free baring of faces in public, especially in Europe and North America. Bit by bit, many countries that have been hard-hit by the coronavirus are opening up and easing their tough, and often unpopular, restrictive measures aimed to fight COVID-19 even as the omicron variant — deemed less severe — has caused cases to skyrocket. The early moves to relax such restrictions evoke a new turning point in a nearly two-year pandemic that has been full of them. Omicron, the Geneva-based World Health Organization says, has fueled m…