Preventing Digi3D.NET from requesting a vertical coordinate reference system when the sensor orientation does not provide one

We have started to simplify everything related to coordinate reference systems in Digi3D.NET. The first step has been to allow to configure that the program does not request the vertical coordinate reference system in case we load an orientation that provides a horizontal system but not a vertical one, as the case explained in the entry The world is in 3D, but nobody remembers the vertical coordinate reference system (yes, the coordinate Z) We just added a new section in the Configuration dialog box named Coordinate Reference Systems which for now has only one option: Ask for sensor's vertical system. If we activate this option and load a photogrammetric model whose orientation provides a horizontal coordinate reference system but not a vertical one, the program will assume that the vertical is Unknown and will not ask us again. If we disable this option, the program will behave as before, i.e. it will ask the user for the vertical system.