Added typedefs and platform-specific i/o.

extras/physfsrwops.h

@@ -29,12 +29,6 @@
 extern "C" {
 #endif
 
-#if (defined _MSC_VER)
-#define __EXPORT__ __declspec(dllexport)
-#else
-#define __EXPORT__
-#endif
-
 /**
  * Open a platform-independent filename for reading, and make it accessible
  *  via an SDL_RWops structure. The file will be closed in PhysicsFS when the