cliff.interactive.InteractiveApp cmdloop does not call the correct method from parenc class

The cmdloop() method in cliff.interactive.InteractiveApp does not call the correct method from the parent class, as it calls the inner _cmdloop() therefore all the logic that cmd2 does is lost. Actually, the method can be dropped, as it does nothing, unless there is a good reason to drop all the logic the cmd2 cmdloop() method introduces. If this is the case, the documentation should be adjusted, as it is misleading.