The ornamental design for a nailfile, as shown and described.
FIG. 1 illustrates a top perspective view of a nail file employing an ornamental design in accordance with the present invention including shading for illustrating a rough surface;
FIG. 2 illustrates a top plan view of the nail file of FIG. 1;
FIG. 3 is a side elevation view of the nail file of FIG. 1;
FIG. 4 is a front elevation view of the nail file of FIG. 1;
FIG. 5 is a side elevation view of the nail file of FIG. 1;
FIG. 6 is a back elevation view of the nail file of FIG. 1; and,
FIG. 7 is a bottom plan view of the nail file of FIG. 1.