Added Table natural sort example to the docs

Author: bvaughn

docs/README.md

@@ -26,4 +26,4 @@ Documentation
 * [Displaying items in reverse order](reverseList.md)
 * [Using AutoSizer](usingAutoSizer.md)
 * [Creating an infinite-loading list](creatingAnInfiniteLoadingList.md)
-* [Displaying a reverse list](reverseList.md)
+* [Natural sort Table](tableWithNaturalSort.md)

docs/tableWithNaturalSort.md

@@ -0,0 +1,75 @@
+By default, `Table` assumes the sortable rows can be sorted in ascending or descending order.
+Clicking a column header the first time will trigger the `sort` callback with a suggested ordering of _ascending_.
+Clicking it a second time will call `sort` with a suggested ordering of _descending_.
+Clicking a third time will suggest _ascending_.
+
+This is often desirable but it has a subtle side effect:
+Once you have sorted a `Table` there is no way to return to an unsorted, "natural" order.
+
+Fortunately `Table` makes it easy for you to implement this functionality within your application code like so:
+
+```jsx
+export default class NaturalSortTable extends Component {
+  constructor (props, context) {
+    super(props, context)
+
+    this.state = {
+      list: props.list // Naturally sorted list
+    }
+  }
+
+  componentWillUpdate (nextProps, nextState) {
+    const {
+      sortBy: prevSortBy,
+      sortDirection: prevSortDirection
+    } = this.state
+
+    if (
+      nextState.sortBy !== prevSortBy ||
+      nextState.sortDirection !== prevSortDirection
+    ) {
+      const { sortBy, sortDirection } = nextState
+
+      let { list } = this.props
+
+      if (sortBy) {
+        list = list.sortBy(item => item[sortBy])
+        if (sortDirection === SortDirection.DESC) {
+          list = list.reverse()
+        }
+      }
+    }
+  }
+
+  render () {
+    const { list, sortBy, sortDirection } = this.state
+
+    return (
+      <Table
+        {...this.props}
+        sort={this._sort}
+        sortBy={sortBy}
+        sortDirection={sortDirection}
+      >
+        {/* <Column>s go here */}
+      </Table>
+    )
+  }
+
+  _sort ({ sortBy, sortDirection }) {
+    const {
+      sortBy: prevSortBy,
+      sortDirection: prevSortDirection
+    } = this.state
+
+    // If list was sorted DESC by this column.
+    // Rather than switch to ASC, return to "natural" order.
+    if (prevSortDirection === SortDirection.DESC) {
+      sortBy = null
+      sortDirection = null
+    }
+
+    this.setState({ sortBy, sortDirection })
+  }
+}
+```