Timebox API (see explanation), first scene is now a timebox, and utils.hpp created.

Timebox Interface created to bring Model, Presenter, FullView and SmallView's classes together.
We can now surf in the hierarchy, and the first scene (QGraphicsScene) is a timebox in fullview.
utils.hpp permit to store viewmode.
Suppress some Qt's dynamic stuff (metaObject) in mainwindow (because not needed actually).