Convert the "search limit" preference over to gconf.

[David Hampton]

Log Message:
-----------
Convert the "search limit" preference over to gconf.

Tags:
----
gnucash-gnome2-dev

Modified Files:
--------------
    gnucash:
        ChangeLog
    gnucash/src/app-utils:
        prefs.scm
    gnucash/src/gnome/schemas:
        apps_gnucash_dialog_common.schemas
    gnucash/src/gnome-search:
        dialog-search.c
    gnucash/src/gnome-utils:
        preferences.glade