Add icons to nav header buttons

although we probably will need a way to remove those soon..  since we don't
have a ton of space up there

src/components/feedback/ByjoveFeedback.vue

@@ -1,6 +1,7 @@
 <template>
   <div>
     <b-button type="is-primary"
+              icon-left="fas fa-comment"
               @click="showFeedback()">
       Feedback
     </b-button>

src/components/menu/ByjoveMenu.vue

@@ -8,8 +8,8 @@
           <button class="button is-primary"
                   :class="{'is-danger': user_is_root}"
                   slot="trigger">
+            <b-icon icon="fas fa-user"></b-icon>
             <span>{{ user.short_name }}</span>
-            <!-- <b-icon icon="menu-down"></b-icon> -->
           </button>
 
           <b-dropdown-item aria-role="listitem" has-link>
@@ -45,7 +45,8 @@
         <b-button v-if="!user"
                   type="is-primary"
                   tag="router-link" to="/login">
-          Login
+          <b-icon icon="fas fa-user"></b-icon>
+          <span>Login</span>
         </b-button>
       </div>