Add new functionality to Large Angle Stability analysis so that a single fixed-weight item in the loadcase can be selected so that automatically the maximum VCG of that item can be found for which the GZ curve still (just) passes all selected stab...

New column in tank calibration tables: vertical height difference between the top of the fluid in the tank and the bottom of the sounding tube (static fluid head) multiplied by tank_fluid_density * acceleration_due_to_gravity in reponse to this qu...