class SimpleMethodMissingDelegate < Object
Create a delegate class that uses method_missing to do its dirty work. Works exactly the same as DelegateClass, but also allows the delegated object to change at run-time (in a type-safe manner).
TODO: If a class has one name, then is aliased to another name, and the original name is changed to point to a different class, then this will not work.
TODO: Constants are not delegated properly.