Add missing nostalgia directory level in src tree

src/nostalgia/core/core.cpp

@@ -0,0 +1,20 @@
+/*
+ * Copyright 2016-2017 gtalent2@gmail.com
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at http://mozilla.org/MPL/2.0/.
+ */
+#include <ox/std/types.hpp>
+#include "gfx.hpp"
+
+namespace nostalgia {
+namespace core {
+
+ox::Error init() {
+	auto err = initGfx();
+	return err;
+}
+
+}
+}