* gnome-settings-xsettings.c: added two new xsettings
	for GTK+ input method preedit and status styles.

	With the other patch for gtk+, the preedit and status styles of
	GTK+ input method are configurable with associated gconf schemas
	keys:
	"/desktop/gnome/interface/gtk-im-preedit-style"
	"/desktop/gnome/interface/gtk-im-status-style"

	Both are set to "callback" by default, and platform's
	packging can have different default by changing
	libgnome's desktop_gnome_interface.schemas.