MANCHESTER, N.H. (AP) — Susan Strickler, the director and CEO of the Currier Museum since 1996, is retiring next June. Under her guidance, the museum gained more than 33,000 square feet of space and added two large communal areas. The museum has expanded its holdings of photography, prints and decorative arts, initiated a collection of craft and added major paintings and sculpture. The Currier's two most popular exhibitions during Strickler's tenure were Maxfield Parrish 1870-1966 (1999) and M.C.