Enable dllexport for Lua API

This allows external libraries to load the Lua API from our executable
even if it is linked statically. This is useful for a Lua debugger which
needs to interact with the Lua API.

lib/lua/luaconf.h

@@ -161,10 +161,22 @@
 
 #else
 
+#ifdef WIN32
+// Export even when building statically to allow external libraries to load the Lua API symbols
+#if defined(LUA_CORE) || defined(LUA_LIB)
+#define LUA_API __declspec(dllexport)
+#else
+#define LUA_API extern
+#endif
+
+#else
+
 #define LUA_API		extern
 
 #endif
 
+#endif
+
 /* more often than not the libs go together with the core */
 #define LUALIB_API	LUA_API