NASHVILLE, Tennessee — Carrie Underwood and Jason Aldean were the big winners, the Judds reunited, and Kelsea Ballerini turned a tough break into a one-woman house party at Monday night’s CMT music awards. “This one’s all about the fans man,” Underwood said as she accepted the belt-buckle CMT trophy for video of the year, a record 25th win for her. …