The ornamental design for a sprayer, as shown and described.
FIG. 1 is a right side elevation of a sprayer that has the design, the left side elevation being a minor image of this view except for the indented section seen on the right side of this figure and an unclaimed element seen in FIGS. 2-4.
FIG. 2 is a front elevation of the sprayer.
FIG. 3 is a rear elevation of the sprayer; and,
FIG. 4 is a top plan view of the sprayer, the bottom of the sprayer not forming part of the claimed design.
The broken line showing of elements of the sprayer is for the purpose of illustrating portions of the sprayer and forms no part of the claimed design.