Change Grayscale to Greyscale in the JPEG viewer and add explanation of the Display Option menu to the manual.

git-svn-id: svn://svn.rockbox.org/rockbox/trunk@20045 a1c6a512-1295-4272-9138-f99709370657

apps/plugins/jpeg/jpeg.c

@@ -326,7 +326,7 @@ bool set_option_dithering(void)
 static void display_options(void)
 {
     static const struct menu_item items[] = {
-        { "Grayscale", set_option_grayscale },
+        { "Greyscale", set_option_grayscale },
         { "Dithering", set_option_dithering },
     };
 

manual/plugins/jpegviewer.tex

@@ -82,6 +82,11 @@ The menu has the following entries.
 \item[Show Playback Menu.] From the playback menu you can control the
 playback of the currently loaded playlist and change the volume of your \dap.
 }
+\opt{lcd_color}{
+\item[Display Options.] From this menu you can force the viewer to render the
+image in greyscale using the \setting{Greyscale} option or set the method of
+dithering used in the \setting{Dithering} submenu.
+}
 \item[Return.] Returns you to the image
 \end{description}