NEW YORK — Drugstore operator Walgreen will offer free clinic visits to the unemployed and uninsured for the rest of the year, providing tests and routine treatment for minor ailments through its walk-in clinics _ though patients will still pay for precriptions. Walgreen said patients who lose their job and health insurance after March 31 will be able to get free treatment at its in-store Take Care clinics for respiratory problems, allergies, infections and skin conditions, among other ailments.