maint: use rows() and columns() to clarify m-files. * gradient.m, interp1q.m, rat.m, tsearchn.m, image.m, imwrite.m, area.m, contourc.m, hist.m, isocolors.m, isonormals.m, meshz.m, print.m, __bar__.m, __go_draw_axes__.m, __interp_cube__.m, __marching_cube__.m, __patch__.m, __print_parse_opts__.m, __quiver__.m, rose.m, shrinkfaces.m, stairs.m, surfnorm.m, tetramesh.m, text.m, deconv.m, spline.m, intersect.m, setdiff.m, setxor.m, union.m, periodogram.m, pcg.m, perms.m: Replace size (x,1) with rows (x) and size(x,2) with columns(x).

--- a/scripts/set/setdiff.m
+++ b/scripts/set/setdiff.m
@@ -82,7 +82,7 @@
         i(idx(dups)) = [];
       endif
       ## Reshape if necessary.
-      if (size (c, 1) != 1 && size (b, 1) == 1)
+      if (rows (c) != 1 && rows (b) == 1)
         c = c.';
       endif
     endif