[AD] d_menu_proc MSG_DRAW handling

[Esaelon@xxxxxxxxxx]

Here I am, again, trying to get my GUI-with-animated-backdrop working.

I managed to get most of it working fairly well, but I was unable to get the 
popup menus from the menu bar to work as expected.  Only the top-level menu 
bar is being redrawn.  I checked the source, and realized that that is all it 
does handle; d_menu_proc will not redraw popup menus in response to a MSG_DRAW.  
I also noticed that there appears to be no way (in the external API, at 
least) to get a menu to redraw at all without using a d_menu_proc DIALOG?

I'll probably try my hand at figuring out how to modify the lib to redraw 
nested popup menus over the next few days, any input on any reasons for the 
current design or opinions on how I believe it should behave would be appreciated. 
:)

More later,
Charles Bilyue'