The ornamental design for a flushplane, as shown and described.
FIG. 1 is a top perspective view of the flush plane. FIG. 2 is a back
elevation view of the flush plane shown in FIG. 1. FIG. 3 is a front
elevation view of the flush plane shown in FIG. 1. FIG. 4 is a side
elevation view of the flush plane shown in FIG. 1. FIG. 5 is a top plan
view of the flush plane shown in FIG. 1; and, FIG. 6 is a bottom plan view
of the flush plane shown in FIG. 1.