[cairo] char* vs. unsigned char*

[Peter Dennis Bartok]

>My inclination is that actual string data, (such as font->family), is
>unlikely to see much arithmetic for which signedness should matter, so
>we should probably use char* for that. That would give compatibility
>with libc.
Not sure it'll matter, but if font->family were ever to contain UTF8 chars 
instead of just ASCII, wouldn't you need unsigned char *?

Cheers,
  Peter