BOSCAWEN, N.H. — Caitlin Hyland’s New Hampshire jail cell looks like those of many of her fellow inmates, featuring family photos, a few books and a cot. But one thing sets it apart: the cage on the floor for a 10-week-old puppy. Hyland, a 28-year-old from Concord, New Hampshire, who is serving time for a drug conviction, is one of four inmates at the Merrimack County jail who are training puppies.