Update Scene File to version 3 since older versions of Workbench will not be...

Update Scene File to version 3 since older versions of Workbench will not be able to properly restore the scenes due to the changes in aspect locking and movement of some window parameters from GuiQt to Brain (simplifies wb_command -show-scene).  This will cause a read error in older versions of wb_view and the error message informs users to update software.