[Mono-dev] Thread shutdown hook patch

[Massimiliano Mantione]

All I can add is that the logging statistical profiler needs it.
As it is in svn it does not crash anymore, but it terminates when the
main thread ends.

So, for instance, it is totally unable to profile "xsp2
--nonstop" (while with this patch, and using the callback, is works
fine).

Thanks!
  Massi