Clear reducing state for REFPROP backend when fractions set; closes #1659
Clear reducing state for REFPROP backend when fractions set; closes #1659

CoolProp/CoolProp,CoolProp/CoolProp,henningjp/CoolProp,CoolProp/CoolProp,CoolProp/CoolProp,henningjp/CoolProp,henningjp/CoolProp,CoolProp/CoolProp,CoolProp/CoolProp,henningjp/CoolProp,henningjp/CoolProp,henningjp/CoolProp,CoolProp/CoolProp,henningjp/CoolProp,henningjp/CoolProp,CoolProp/CoolProp