build: Rename __go_draw_XXX to __gnuplot_draw_XXX for clarity. * scripts/plot/util/private/__gnuplot_draw_axes__.m: Renamed from __go_draw_axes__.m * scripts/plot/util/private/__gnuplot_draw_figure__.m: Renamed from __go_draw_figure__.m * __scatter__.m, __gnuplot_drawnow__.m: Update scripts to use new names. * scripts/plot/util/module.mk: Use new file names in build system.