Ability to assign multiple refs (1 & 2) for indoor, futsal, or arena soccer#930

There should be an option to assign Ref 1, Ref 2, Ref 3, etc that can be used for leagues that don’t implement assistant referees. This would be especially helpful for futsal, indoor soccer, and arena soccer. This way, when sorting previous games by position, we can easily select which of those positions we want to sort by.