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/App/Range.h

@@ -24,6 +24,9 @@
 #define RANGE_H
 
 #include <string>
+#ifndef FC_GLOBAL_H
+#include <FCGlobal.h>
+#endif
 
 namespace App {