Add unselected state for relationship magnitude
Add unselected state for relationship magnitude

This forces the user to select an option.

This required adding a view state to hold on to the currently selected
relationship vector, since we can't create a relationship until we
have both the vector and the scalar.

[#117182021]
concord-consortium/building-models,concord-consortium/building-models,concord-consortium/building-models,concord-consortium/building-models,concord-consortium/building-models