FIG. 1 is a perspective view of a shower control showing our design; FIG. 2 is a front elevational view thereof; FIG. 3 is a left side elevational view thereof; the right side elevational view being a mirror image thereof; FIG. 4 is a top plan view thereof; and, FIG. 5 is a bottom plan view thereof. The broken lines in the drawings represent unclaimed portions of the design and form no part thereof.