message: Update FixedSizeString.h
  Minor change in hash class
diff: @@ -361,9 +361,9 @@ using String2K = FixedSizeString<2047>;
  namespace std {
  template<>
  -struct hash<typename hmdf::String64> {
  +struct hash<typename hmdf::VirtualString> {
  - inline size_t operator() (const hmdf::String64 &key) const noexcept {
  + inline size_t operator()(const hmdf::VirtualString &key) const noexcept {
  return (key.hash());
  }
  