store unvanquished minimap in minimaps/<mapname>.tga

Hi, if I do that:

q3map2 -game xonotic -minimap maps/<mapname>.bsp

q3map2 generates a minimap here with this path:

gfx/<mapname>_mini.tga

It could be very good if we can do this too:

q3map2 -game unv -minimap maps/<mapname>.bsp

To get:

minimaps/<mapname>.tga

But I don't know how to do it. @Ingar, do you know how to do it?

Also, Unvanquished needs a .arena file generated from some numbers we can find in q3map2's output, it could be very good if q3map2 being able to generate this file too.