Moves more stuff from windows.h.
- include/winuser.h - interface relevant to user32.spec
- include/wine/winuser16.h - the old 16 bit interface (internal use)
- include/winbase.h - some minor updates to keep things coherent.
- Lot of other files made to include wine/winuser16.h, which is no
  longer included from windows.h

diff --git a/misc/spy.c b/misc/spy.c
index 3996003..e9682bd 100644
--- a/misc/spy.c
+++ b/misc/spy.c
@@ -7,7 +7,7 @@
 
 #include <stdlib.h>
 #include <string.h>
-#include "windows.h"
+#include "wine/winuser16.h"
 #include "win.h"
 #include "module.h"
 #include "options.h"