Merge branch 'documentation' into release-1.4.2

Author: ecorreia

README.md

@@ -68,7 +68,11 @@ return (
     <ul>
         <FlatList
           list={this.props.people}
-          renderItem={this.renderPerson}/>
+          renderItem={this.renderPerson}
+          renderWhenEmpty={() => <div>List is empty!</div>}
+          sortBy={["firstName", {by: "lastName", descending: true}]}
+          groupBy={person => person.info.age > 18 ? 'Over 18' : 'Under 18'}
+        />
     </ul>
 )
 ```