In October, International Textile Group, acquired by a private equity firm a year ago, announced plans to close the storied Cone Denim White Oak plant in Greensboro, N.C. That factory was a 112-year-old shrine to bluejeans and the last major manufacturer of selvage denim in the United States. The blow was most immediate among the plant’s roughly 200 employees, as well as in Greensboro — a.k.a. “Jeansboro” — itself. The company filed notice that it would lay off 208 people. Customers were also distressed.