continue consolidating packages, converting various pieces to react

Packages/ohif-viewerbase/client/components/viewer/ViewerMain/ViewerMain.js

@@ -3,10 +3,10 @@ import { Session } from 'meteor/session';
 import { OHIF } from 'meteor/ohif:core';
 // Local Modules
 import { unloadHandlers } from '../../../lib/unloadHandlers';
-import { ResizeViewportManager } from '../../../lib/classes/ResizeViewportManager';
 import { LayoutManager } from '../../../lib/classes/LayoutManager';
-import { StudyPrefetcher } from '../../../lib/classes/StudyPrefetcher';
-import { StudyLoadingListener } from '../../../lib/classes/StudyLoadingListener';
+
+const { StudyLoadingListener, StudyPrefetcher, ResizeViewportManager } = OHIF.classes;
+
 import './ViewerMain.styl';
 
 import { Component } from 'react';