We claim the ornamental design for a timer, as shown and described.
FIG. 1 is a perspective view of a timer according to our new design;
FIG. 2 is a top view of the timer shown in FIG. 1;
FIG. 3 is a bottom view of the timer shown in FIG. 1;
FIG. 4 is a front view of the timer shown in FIG. 1;
FIG. 5 is a rear view of the timer shown in FIG. 1;
FIG. 6 is a right side view of the timer shown in FIG. 1; and,
FIG. 7 is a left side view of the timer shown in FIG. 1.
The ornamental design which is claimed is shown in solid lines in the drawings. Broken lines in the drawings are for illustrative purposes only and form no part of the claimed design.