`BeebState`

[tom-seddon]

Does this need to exist any more? It has a name, and a pointer to a state, and it derives from enable_shared_from_this.

The name could be part of the state (somehow).

Would enable_shared_from_this still be useful enough to warrant a separate structe? Could/should BBCMicro::CloneState return shared_ptr<BBCMicroUniqueState> (then follow through)?

I think shared_ptr will remain necessary as these pointers are passed between main thread and Beeb thread.