Updated property references for text and graphics functions (bug #50247) * /scripts/gui/dialog.m, waitbar.m: added Figure Properties reference * /scripts/gui/setappdata.m: added getappdata propery reference * /scripts/image/imagesc.m: added Image Properties reference * /scripts/image/imread.m: added Representing Images reference * /scripts/plot/appearance/clabel.m, gtext.m, xlabel.m, ylabel.m, zlabel.m: added Text Properties reference * /scripts/plot/appearance/legend.m: added Graphics Object Properties reference * /scripts/plot/appearance/private/__gnuplot_legend__.m: added Graphics Object Properties reference * /scripts/plot/draw/area.m, bar.m, barh.m, fill.m, hist.m, rectangle.m, scatter.m, scatter3.m, tetramesh.m, trimesh.m, trisurf.m: added Patch Properties reference * /scripts/plot/draw/colorbar.m: add Axes Properties reference * /scripts/plot/util/hggroup.m, subplot.m: added Axes Properties reference * /scripts/plot/draw/fplot.m, plot.m, plot3.m, stairs.m, stem.m, stem3.m: add/update Line Properties reference * /scripts/plot/draw/mesh.m, meshc.m, meshz.m, surf.m, surfc.m, surfnorm.m, waterfall.m: add/update Surface Properties reference * /doc/interpreter/plot.txi: removed redundant text properties link

--- a/scripts/plot/draw/fplot.m	Sat Sep 12 13:49:50 2020 -0700
+++ b/scripts/plot/draw/fplot.m	Tue Feb 18 21:35:39 2020 -0500
@@ -59,6 +59,9 @@
 ## in pairs.  These arguments are applied to the line objects drawn by
 ## @code{plot}.
 ##
+## The full list of line properties is documented at
+## @ref{Line Properties}.
+##
 ## If the first argument @var{hax} is an axes handle, then plot into this axes,
 ## rather than the current axes returned by @code{gca}.
 ##