Improve demo

demo/index.js

@@ -1,16 +1,10 @@
 import Vue from 'vue'
 import axios from 'axios'
-import AudioRecorder from '../src/audio-recorder'
+import app from './app'
 
-Vue.config.productionTip = false
 Vue.prototype.$http = axios
 
 new Vue({
   el: '#app',
-  components: {AudioRecorder},
-  methods: {
-    callback (msg) {
-      console.debug('Event: ', msg)
-    }
-  }
+  render: h => h(app)
 })