audit small applets and mark some of them as NOFORK.

Put big scary warnings in relevant places.

coreutils/true.c

@@ -10,9 +10,10 @@
 /* BB_AUDIT SUSv3 compliant */
 /* http://www.opengroup.org/onlinepubs/007904975/utilities/true.html */
 
-#include <stdlib.h>
 #include "busybox.h"
 
+/* This is a NOFORK applet. Be very careful! */
+
 int true_main(int argc, char **argv);
 int true_main(int argc, char **argv)
 {