Hide timeline if user isn't logged in.

src/components/nav_panel/nav_panel.js

 const NavPanel = {
+  computed: {
+    loggedIn () {
+      return this.$store.state.users.currentUser
+    }
+  }
 }
 
 export default NavPanel

src/components/nav_panel/nav_panel.vue

@@ -2,7 +2,7 @@
   <div class="nav-panel">
     <div class="panel panel-default">
       <ul>
-        <li ng-if='currentUser'>
+        <li v-if='loggedIn'>
           <router-link to='/main/friends'>
             Timeline
           </router-link>