title: app.message returns undefined in console using Vue in Laravel
body: <p>I've just started learning Vue, and have been following there <a href="https://v2.vuejs.org/v2/guide/" rel="nofollow noreferrer">intro guide</a>, but am stuck at the:</p>
  <blockquote>
  <p>Just open up your browser’s JavaScript console and set app.message to
  a different value.</p>
  </blockquote>
  <p>I tried <code>app.message = 'test'</code> in Chrome's console, and it returns <code>&quot;test&quot;</code>, but the text doesn't change in the browser.</p>
  <p>Also when I just run <code>app.message</code> before setting it to &quot;test&quot;, it returns <code>undefined</code>.</p>
  <p><strong>app.js</strong></p>
  <pre><code>require('./bootstrap');
  
  const app = new Vue({
      el: '#app',
      data: {
        message: 'Hello Vue!'
      }
  });
  </code></pre>
  <p><strong>./bootstrap</strong></p>
  <pre><code>window._ = require('lodash');
  
  window.$ = window.jQuery = require('jquery');
  require('bootstrap-sass');
  
  window.Vue = require('vue');
  require('vue-resource');
  
  Vue.http.interceptors.push((request, next) =&gt; {
      request.headers.set('X-CSRF-TOKEN', Laravel.csrfToken);
  
      next();
  });
  </code></pre>
  <p><strong>test.blade.php</strong></p>
  <pre><code>@extends('layouts.app')
  
  @section('content')
  &lt;div id=&quot;app&quot;&gt;
    @{{ message }}
  &lt;/div&gt;
  @endsection
  </code></pre>
  <p>I'm guessing its something to do with what Laravel does since when I start a standalone html file it works as Vue says. I'm also new to Laravel so not to sure what's going on here.</p>
  <p>Using Vue 2 and Laravel 5.3</p>