The ornamental design for a picturehanger, as shown and described.
FIG. 1 is a front perspective view of a picture hanger showing the new design;
FIG. 2 is a top view thereof;
FIG. 3 is a right side view thereof, the left side view being a mirror image; and,
FIG. 4 is a front view thereof.
The broken lines within the bounds of the picture hanger represent unclaimed portions of the design that form no part of the claimed design. The broken lines outside the bounds of the picture hanger represent environment that forms no part of the claimed design.