Refs #9371 View and model are now presenter members

the presenter now keeps the view and model as member variables. Load() is used to put the model into the view.
Refs #9371 Interface now loads tables into itself

The interface will now load and display any tableworkspaces in reflectometry format already in the ADS.
Refs #9371 Unit tests updated

The unit tests have been updated wiht the following:

The null object now tests notify() rather than load() as notify is all the view should do and load() is now private.

The concrete class now tests three fail cases where the table isn't in a valid format.