Add command to delete items
Selection will add items when ctrl is pressed
Selected items can be seen dynamically during the selection

	modified:   Sources/Algorithme/algorithmeScene.cpp
	modified:   Sources/Algorithme/algorithmeScene.hpp
	modified:   Sources/Interface/mainwindow.cpp
	modified:   Sources/Interface/mainwindow.hpp
	modified:   Sources/Interface/mainwindow.ui