Added phone socket texture.
Added MachineWidget and MachineScene.
Working on machine.
Scenes can ask views to replace them with their counterparts.
Added MouseWheelEvent. Swapped some code in View.cpp
Added keyboard modifier data to Event base class.
Doing simple view zooming and scrolling with mouse wheel events.
Refactored most of the MouseView class into the parent Event class...
because we want to track mouse status with key events to deliver them
to appropriate places.
Sending proper mouse positions for every event kind.
Using SDL_GetMouseState where mouse state is not available
via SDL_Event structure.