* gnome/vpn-properties/nm-vpn-ui-interface.h: Require users of this
        API to define NM_VPN_API_SUBJECT_TO_CHANGE to acknowledge API churn.
        Also add new methods can_export, import_file and export.

        * gnome/vpn-properties/nm-vpn-properties.glade: Add an Export button
        to the main UI

        * gnome/vpn-properties/nm-vpn-properties.c:
        Define NM_VPN_API_SUBJECT_TO_CHANGE so we can actually include
        nm-vpn-ui-interface.h.
        (update_edit_del_sensitivity): Also update "Export" sensitivity
        (add_vpn_connection): Also add new SVC_NAME column
        (import_settings): New function
        (retrieve_data_from_selected_connection): New function
        (edit_cb): Use retrieve_data_from_selected_connection to simplify
        this function
        (export_cb): New function
        (init_app): Also setup the "export" widget
        (main): Support the --import-service and --import-file commandline
        arguments

        * gnome/libnm_glib/libnm_glib.c (libnm_glib_dbus_filter): Also support
        D-BUS 0.34


git-svn-id: http://svn-archive.gnome.org/svn/NetworkManager/trunk@700 4912f4e0-d625-0410-9fb7-b9a5a253dbdc