message: Fix ObjLink::operator<() and operator>()
diff: @@ -286,11 +286,20 @@ public:
  }
  bool operator<(const ObjLink& rhs) const
  {
  - return m_table_key < rhs.m_table_key || m_obj_key < rhs.m_obj_key;
  + if (m_table_key < rhs.m_table_key) {
  + return true;
  + }
  + else if (m_table_key == rhs.m_table_key) {
  + return m_obj_key < rhs.m_obj_key;
  + }
  + else {
  + // m_table_key >= rhs.m_table_key
  + return false;
  + }
  }
  bool operator>(const ObjLink& rhs) const
  {
  - return m_table_key > rhs.m_table_key || m_obj_key > rhs.m_obj_key;
  + return (*this != rhs) && !(*this < rhs);
  }
  TableKey get_table_key() const
  {
  