Add required import

Author: jbrodriguez

src/lib/InputComponent.js

@@ -1,7 +1,7 @@
 'use strict';
 
 import React from 'react';
-import ReactNative from 'react-native';
+import ReactNative, { Platform } from 'react-native';
 import {Field} from './Field.js';
 
 const {View, StyleSheet, TextInput, Text} = ReactNative;