NLSR

After reviewing the codebase and Ashlesh pointing something out, I see that it is not possible to cleanly replace the face-direct registration with the dispatcher in NLSR. This is because the dispatcher registration is asynchronous and does not provide a callback on top-level prefix registration success.
Currently the LSDBDatasetInterestHandler and PrefixUpdateProcessor set Face Interest filters directly. This needs to be done after the prefix registration, making it unsuitable to register the prefix with the dispatcher.

However, these two things can be refactored as prefix registrations with the dispatcher, which would allow the Face prefix registration itself to be moved into the dispatcher. The necessary refactoring would be to make these two modules accept some derived class of ControlParameters. This should not be too much work, because both of these modules at some point create a ControlParameters object out of the Interest they received.

I could have done it, but that's a little outside of the scope of this task.