move instance of MessageQueue export to ts/session folder

preload.js

@@ -160,7 +160,6 @@ window.setPassword = (passPhrase, oldPhrase) =>
 
 window.passwordUtil = require('./app/password_util');
 window.libsession = require('./ts/session');
-window.libsession.getMessageQueue = require('./ts/session/sending/instance').getMessageQueue;
 
 // We never do these in our code, so we'll prevent it everywhere
 window.open = () => null;

ts/session/index.ts

@@ -1,5 +1,6 @@
 import * as Messages from './messages';
 import * as Protocols from './protocols';
 import * as Types from './types';
+import { getMessageQueue } from './instance';
 
-export { Messages, Protocols, Types };
+export { Messages, Protocols, Types, getMessageQueue };

ts/session/instance.ts

@@ -1,4 +1,4 @@
-import { MessageQueue } from './MessageQueue';
+import { MessageQueue } from './sending/';
 
 let messageQueue: MessageQueue;