gst/gst.c: if we have fork, fork while reading/rebuilding the registry so the parent...

gst/gst.c: if we have fork, fork while reading/rebuilding the registry so the parent doesn't take the hit of having a...

Original commit message from CVS:

* gst/gst.c: (init_post):
if we have fork, fork while reading/rebuilding the registry
so the parent doesn't take the hit of having all plugins loaded
in memory.  Fixes #342777.
* configure.ac:
Check if we have fork()
* win32/common/config.h.in:
no fork() on win32