Added standard InChi key & string for Sulfur Dioxide
Added standard InChi key & string for Sulfur Dioxide

Values obtained from: https://pubchem.ncbi.nlm.nih.gov/compound/1119#section=Names-and-Identifiers
henningjp/CoolProp,CoolProp/CoolProp,CoolProp/CoolProp,henningjp/CoolProp,CoolProp/CoolProp,CoolProp/CoolProp,henningjp/CoolProp,CoolProp/CoolProp,CoolProp/CoolProp,henningjp/CoolProp,henningjp/CoolProp,henningjp/CoolProp,henningjp/CoolProp,CoolProp/CoolProp,henningjp/CoolProp,CoolProp/CoolProp