Add Advanced menu, add copyright header to menus.xml
Abstract Settings... GtkGrid into generic grid-building functions
output: overhaul output list management, mockup "Add Outputs" dialog
Hook up "use bitcoind to obtain addresses" checkbox

If you uncheck it, you can't get any addresses :)
'Add outputs' dialog can delete addresses

Still can't add them, though ;)
gtk: enable manual adding of addresses

There is no verification of the entered addresses. This should
probably be addressed at some point, but for now it is fine,
they are easy to delete.