pthreads patch

[Chris Morgan]

After adding some printfs I discovered that jack was locking up at a call to 
pthread_create.  Jack also uses plenty of other pthreads functions so I tried 
to implement as many as possible.  Just wanted to run this patch by people 
before submitting to wine-patches.

scheduler/pthread.c, thread.c,
server/thread.c, request.h,
include/winbase.h, include/wine/server_protocol.h,
dlls/kernel/kernel32.spec
Chris Morgan 
Implement OpenThread().  Implement a few pthreads functions.

Patch is X11 as Ove helped out.