Revert #65

(fix #117)
PR #65 removed the escape character, making vue-cli/handlebars replace this interpolation instead of eaving it to Vue.

template/src/App.vue

@@ -1,7 +1,7 @@
 <template>
   <div id="app">
     <img src="./assets/logo.png">
-    <h1>{{ msg }}</h1>
+    <h1>\{{ msg }}</h1>
     <h2>Essential Links</h2>
     <ul>
       <li><a href="https://vuejs.org" target="_blank">Core Docs</a></li>