Adding webpack code splitting (#3377)

webapp/components/claim/claim_controller.jsx

@@ -3,7 +3,7 @@
 
 import React from 'react';
 import {FormattedMessage} from 'react-intl';
-import {Link} from 'react-router';
+import {Link} from 'react-router/es6';
 
 import logoImage from 'images/logo.png';
 

webapp/components/claim/components/oauth_to_email.jsx

@@ -7,7 +7,7 @@ import Client from 'utils/web_client.jsx';
 import React from 'react';
 import ReactDOM from 'react-dom';
 import {FormattedMessage} from 'react-intl';
-import {browserHistory} from 'react-router';
+import {browserHistory} from 'react-router/es6';
 
 export default class OAuthToEmail extends React.Component {
     constructor(props) {