GraphView window title now contains center object identification
The size and position of the main window when maximalized is not stored, but the information about the maximalization itself is.
When inner window is (de)maximalized, textflow's layoutChildren is called, so all mouse events should be properly handled
Added menu item (shortcut CTRL+ALT+HOME) to reset main window size and position to reasonable defaults.
Added center button to graph view
Proper pagination indicator instead of dummy
When adding new relation, slots for previous roles are reserved.