Add logout button.

src/App.js

@@ -29,6 +29,9 @@ export default {
     },
     scrollToTop () {
       window.scrollTo(0, 0)
+    },
+    logout () {
+      this.$store.dispatch('logout')
     }
   }
 }

src/App.vue

@@ -8,6 +8,7 @@
         <div class='item right'>
           <user-finder></user-finder>
           <router-link :to="{ name: 'settings'}"><i class="icon-cog"></i></router-link>
+          <a href="#" v-if="currentUser" @click.prevent="logout"><i class="icon-logout" title="Logout" ></i></a>
         </div>
       </div>
     </nav>

src/modules/users.js

@@ -26,6 +26,9 @@ export const mutations = {
   setCurrentUser (state, user) {
     state.currentUser = merge(state.currentUser || {}, user)
   },
+  clearCurrentUser (state) {
+    state.currentUser = false
+  },
   beginLogin (state) {
     state.loggingIn = true
   },
@@ -66,6 +69,11 @@ const users = {
         store.commit('setUserForStatus', status)
       })
     },
+    logout (store) {
+      store.commit('clearCurrentUser')
+      store.dispatch('stopFetching', 'friends')
+      store.commit('setBackendInteractor', backendInteractorService())
+    },
     loginUser (store, userCredentials) {
       return new Promise((resolve, reject) => {
         const commit = store.commit