`Store address' user interface

[Peter Bloomfield <PeterBloomfield MindSpring com>]

The `Store address' dialog now offers a notebook with all of the 
addresses in all of the selected messages. It currently sports two 
buttons:
- Save in address book
- Close
the latter being a GNOME_STOCK button, with an icon. The `Save...' 
button leaves the dialog open, so that you can choose and save more 
addresses from the notebook.

I mostly want to save only one address, so it would be nice to have an 
`OK' button, which would save the current address in the address book, 
and close the dialog. Would changing the buttons to:
- OK
- Save
- Close
be confusing?  And is this order conventional?