Remove references to deleted data structures.

[David Hampton]

Log Message:
-----------
Remove references to deleted data structures.  Gnucash now compiles
against g-wrap-1.9.6 as well as g-wrap-1.3.

Tags:
----
gnucash-gnome2-dev

Modified Files:
--------------
    gnucash:
        ChangeLog
    gnucash/src/gnome-utils:
        gw-gnome-utils-spec.scm