Optimized include/*.h: (recursively) include all headers needed by
this .h file, but only those. Necessary fixes to a lot of .c files,
started optimizing "windows.h" away from some of them. Moved
GetCurrentTask prototype to wine/winbase16.h.

diff --git a/include/vfw.h b/include/vfw.h
index 6375419..1bad215 100644
--- a/include/vfw.h
+++ b/include/vfw.h
@@ -1,9 +1,10 @@
 #ifndef __WINE_VFW_H
 #define __WINE_VFW_H
 
-#include <wintypes.h>
-#include <driver.h>
-#include <objbase.h>
+#include "wintypes.h"
+#include "wingdi.h"
+#include "driver.h"
+#include "objbase.h"
 
 #define VFWAPI	WINAPI
 #define VFWAPIV	WINAPIV