The free agent period officially opened at 5 p.m. yesterday, and already we’ve heard the rumblings of the winter hot stove as it begins to heat up. Most of the moves made are of the run-of-the-mill roster housekeeping variety — tendering qualifying offers, placing players on waivers to clear 40-man roster space, and decisions on player and club options — and the Yankees have been one of the busier teams in that regard. With the CBA expiration looming, it’s no surprise to see teams attend to some business before a potential transactions freeze descends on the winter.