Rewrite to remove dependence on rendezvous and its bizarre

data structures.  Makes it easier to use pthreads too.
Still need to add code for non-pthreads systems.

Just a checkpoint to switch work to another machine.

src/libthread/main.c

@@ -40,7 +40,7 @@ main(int argc, char **argv)
 
 //_threaddebuglevel = (DBGSCHED|DBGCHAN|DBGREND)^~0;
 	_systhreadinit();
-	_qlockinit(_threadrendezvous);
+	_qlockinit(_threadsleep, _threadwakeup);
 	_sysfatal = _threadsysfatal;
 	notify(_threadnote);
 	if(mainstacksize == 0)
@@ -49,8 +49,9 @@ main(int argc, char **argv)
 	a = _threadmalloc(sizeof *a, 1);
 	a->argc = argc;
 	a->argv = argv;
-
+malloc(10);
 	p = _newproc(mainlauncher, a, mainstacksize, "threadmain", 0, 0);
+malloc(10);
 	_schedinit(p);
 	abort();	/* not reached */
 	return 0;
@@ -61,7 +62,9 @@ mainlauncher(void *arg)
 {
 	Mainarg *a;
 
+malloc(10);
 	a = arg;
+malloc(10);
 	threadmain(a->argc, a->argv);
 	threadexits("threadmain");
 }