Starts a switch to reflectable-style runtime options.

The Amstrad CPC and ZX80/81 have made the jump so far, subject to caveats. The macOS build is unlikely currently to work properly.

Machines/MasterSystem/MasterSystem.cpp

@@ -378,7 +378,7 @@ class ConcreteMachine:
 		}
 
 		// MARK: - Configuration options.
-		std::unique_ptr<Reflection::Struct> get_options(OptionsType type) final {
+		std::unique_ptr<Reflection::Struct> get_options() final {
 			return nullptr;
 		}