Added wacca stub code

mercuryio/config.h

@@ -0,0 +1,17 @@
+#pragma once
+
+#include <stddef.h>
+#include <stdint.h>
+
+#include <stdbool.h>
+
+struct mercury_io_config {
+    uint8_t vk_test;
+    uint8_t vk_service;
+    uint8_t vk_1p_btn[9];
+    uint8_t vk_2p_btn[9];
+};
+
+void mercury_io_config_load(
+        struct mercury_io_config *cfg,
+        const wchar_t *filename);