utils: add Result / Option types

Add some Rust-style Result/Option types, based on TartanLlama's
expected, optional classes.

There's std::optional of course, but we can't depend on C++17 yet.

lib/utils/mu-option.hh

@@ -0,0 +1,26 @@
+/*
+ * Created on 2020-11-08 by Dirk-Jan C. Binnema <dbinnema@logitech.com>
+ *
+ * Copyright (c) 2020 Logitech, Inc.  All Rights Reserved
+ * This program is a trade secret of LOGITECH, and it is not to be reproduced,
+ * published, disclosed to others, copied, adapted, distributed or displayed
+ * without the prior authorization of LOGITECH.
+ *
+ * Licensee agrees to attach or embed this notice on all copies of the program,
+ * including partial copies or modified versions thereof.
+ *
+ */
+
+#ifndef MU_OPTION__
+#define MU_OPTION__
+
+#include "optional.hpp"
+
+
+namespace Mu {
+
+/// Either a value of type T, or nothing.
+template <typename T> using Option=tl::optional<T>;
+
+}
+#endif /*MU_OPTION__*/