feat(PDF):Add PDF viewer (#2730)

Display DICOM encapsulated PDF documents in a PDF viewer.
Addressed the remaining PR comments, and am merging this.

platform/viewer/src/appInit.js

@@ -17,7 +17,6 @@ import {
   errorHandler
   // utils,
 } from '@ohif/core';
-import ConfigPoint from 'config-point';
 
 /**
  * @param {object|func} appConfigOrFunc - application configuration, or a function that returns application configuration
@@ -50,10 +49,6 @@ function appInit(appConfigOrFunc, defaultExtensions) {
     appConfig,
   });
 
-  // Load the default theme settings
-  const defaultTheme = config && config.defaultTheme || 'theme';
-  ConfigPoint.load(defaultTheme, '/theme', 'theme');
-
   servicesManager.registerServices([
     UINotificationService,
     UIModalService,