tools/gst-launch.c (main): Handle err == NULL. gst/gst.c (init_post, ensure_current_registry) (ensure_current_registr...

Original commit message from CVS:
2006-07-08  Andy Wingo  <wingo@pobox.com>

* tools/gst-launch.c (main): Handle err == NULL.

* gst/gst.c (init_post, ensure_current_registry)
(ensure_current_registry_forking)
(ensure_current_registry_nonforking): Reduce #ifdef ratnest by
factoring out the registry scanning into separate functions. Don't
fork for the rescan is GST_REGISTRY_FORK=no; useful in debugging.
Better environment var name/interface suggestions accepted.