Chapter 5 - Missing loading prop on withData function

On chapter 6 page 83 the following `withData` function is show: 

```
const withData = graphql(SECTION_QUERY, {
  props: ({ data: { section }}) => ({ section })
})
```

It should be: 

```
const withData = graphql(SECTION_QUERY, {
  props: ({ data: { section, loading }}) => ({ section, loading })
})
```