message: indicate compare sort direction
diff: @@ -338,7 +338,8 @@ class Compare extends React.Component<Props, State> {
  onMouseOver={() => this.setHighlight(stat.id)}
  onClick={() => this.sort(stat.id)}
  >
  - {stat.displayProperties.name}
  + {stat.displayProperties.name}{' '}
  + {stat.id === sortedHash && (this.state.sortBetterFirst ? '>' : '<')}
  </div>
  ))}
  </div>
  