Add GStreamer-based (cdparanoia) option. Based on work from Iain Holmes

* configure.in:
* gnome-cd/Makefile.am:
* gnome-cd/gnome-cd.c: (main):
Add GStreamer-based (cdparanoia) option. Based on work from Iain
Holmes <bugs@prettypeople.org>. Fixes bug #51152.