Use watcher instead of event for meal loading

src/App.vue

@@ -2,11 +2,11 @@
   <div id="app">
     <h1>Essen in Göttingen</h1>
 
-    Wo? <select v-model="where" @click="updateRoute">
+    Wo? <select v-model="where">
       <option v-for="mensa in mensen" :value="mensa.url">{{mensa.name}}</option>
     </select>
 
-    Wann? <select v-model="when" @click="updateRoute">
+    Wann? <select v-model="when">
       <option v-for="day in days" :value="day" :key="day">{{dayOfWeek[day]}}</option>
     </select>
     <router-view></router-view>
@@ -43,6 +43,10 @@ export default {
       when: '' + new Date().getDay()
     }
   },
+  watch: {
+    'where': 'updateRoute',
+    'when': 'updateRoute'
+  },
   methods: {
     updateRoute () {
       this.$router.push(`/${this.where}/${this.when}`)