add guiicons to make-updates

the guiicons folder contains the images used by npc menus;

for example:
```
mes "Please choose an option.";
menu
    "next|Do something.", L_Next,
    "quit|Do nothing.", L_Quit;
```
in this example, **next** is **graphics/guiicons/next.png** and **quit** is **graphics/guiicons/quit.png**