The ornamental design for a caprack, as shown and described.
FIG. 1 is a front perspective view of a cap rack;
FIG. 2 is a front elevation view thereof;
FIG. 3 is a left elevation view thereof, the right elevation view being the mirror image thereof;
FIG. 4 is a top plan view thereof;
FIG. 5 is a bottom plan view thereof; and,
FIG. 6 is the left elevation view, shown in use.
The evenly-sized broken lines showing a cap, a supporting surface, and a fastener depict environmental subject matter that forms no part of the claimed design, while the remaining evenly-sized broken lines shown in the drawings depict portions of the cap rack that form no part of the claimed design, while the unevenly-sized broken lines consisting of dash-dot-dash lines in the drawings depict the boundary of the claimed invention and it is understood that the claim extends to the boundary that forms no part of the claimed design.