Fix goback button

v4.3.0

web/documentserver-example/nodejs/helpers/docManager.js

@@ -32,6 +32,12 @@ const guidManager = require("./guidManager");
 const configServer = require('config').get('server');
 const storageFolder = configServer.get('storageFolder');
 const os = require("os");
+const readline = require('readline');
+
+const rl = readline.createInterface({
+  input: process.stdin,
+  output: process.stdout
+});
 
 let docManager = {};