Move worker initialization to background.js

Not sure why I put it in panel controller. Probably an oversight.

// FREEBIE

js/background.js

@@ -28,6 +28,8 @@
         appWindow.close();
     });
 
+    textsecure.protocol_wrapper.startWorker();
+
     storage.fetch();
     storage.onready(function() {
         var messageReceiver;

js/panel_controller.js

@@ -21,8 +21,6 @@
 
     window.Whisper = window.Whisper || {};
 
-    textsecure.protocol_wrapper.startWorker();
-
     var conversations = new Whisper.ConversationCollection();
 
     window.inbox = new Whisper.ConversationCollection([], {