gconf-database-dbus: Allow setting the gconf values to the schema default
gconf-database-dbus: Allow setting the gconf values to the schema default

Fixes: https://bugzilla.gnome.org/show_bug.cgi?id=655954

GNOME/gconf,hyperair/gconf-gdbus,GNOME/gconf,hyperair/gconf-gdbus,GNOME/gconf,GNOME/gconf,hyperair/gconf-gdbus,hyperair/gconf-gdbus