renamed:    main/machine_scenes.cpp -> main/MachineScene.cpp
	renamed:    main/machine_scenes.h -> main/MachineScene.h
	renamed:    main/machine_widgets.cpp -> main/MachineWidget.cpp
	renamed:    main/machine_widgets.h -> main/MachineWidget.h
Added beforeDestruction() hook to Disposable.
Added proper rendering context setup.

Also working on wire plugging.