Base: split export/import macros from FCConfig.h and move them to FCGlobal.h

The FCGlobal.h can be included in a Global.h header file of an extension module.

The reason is that some IDEs (e.g. QtCreator) fails to detect the export/import macros when only defined in the PreCompiled.h files and thus raise a parser warning.

src/Base/StackWalker.h

@@ -36,7 +36,10 @@
 // so we need not to check the version (because we only support _MSC_VER >= 1100)!
 #pragma once
 
-#include <windows.h>
+#include <Windows.h>
+#ifndef FC_GLOBAL_H
+#include <FCGlobal.h>
+#endif
 
 // special defines for VC5/6 (if no actual PSDK is installed):
 #if _MSC_VER < 1300