This is just a quick hack... call it with the path to your GNUMail
address book (usually ~/GNUstep/Library/GNUMail/AddressBook). It will
try to read everything from there and put it into Addresses format.

The program uses the following heuristic to split GNUMail's name field
into Addresses's first/last name fields:

1. Name contains a ",": Split it at the "," and put the first part
   into last name and the second part into first name.

	"Müller, Fritz" -> "Müller", "Fritz"

2. Name doesn't contain a ",": Split it at spaces and put the last
   part into last name and everything else into first name.

	"Johnny B. Goode" -> "Goode", "Johnny B."