Add innerRef to KeyboardAwareProps (index.d.ts) (#300)

Author: taichi-jp

index.d.ts

@@ -7,6 +7,14 @@ import * as React from 'react'
 import { ScrollViewProperties, ListViewProperties, FlatListProperties, SectionListProperties } from 'react-native'
 
 interface KeyboardAwareProps {
+  /**
+     * Catches the reference of the component.
+     *
+     *
+     * @type {function}
+     * @memberof KeyboardAwareProps
+     */
+  innerRef?: (ref: JSX.Element) => void
   /**
      * Adds an extra offset that represents the TabBarIOS height.
      *