Implement a disconnected indicator

Fixes #451

.meteor/.gitignore

@@ -1 +1,2 @@
+dev_bundle
 local

client/components/main/header.jade

@@ -45,3 +45,12 @@ template(name="header")
         else
           a.wekan-logo(href="{{pathFor 'home'}}" title="{{_ 'header-logo-title'}}")
             img(src="{{pathFor '/wekan-logo-header.png'}}" alt="Wekan")
+
+  if appIsOffline
+    +offlineWarning
+
+template(name="offlineWarning")
+  .offline-warning
+    p
+      i.fa.fa-warning
+      | {{_ 'app-is-offline'}}

client/components/main/header.js

@@ -6,6 +6,10 @@ Template.header.helpers({
   hideLogo() {
     return Utils.isMiniScreen() && Session.get('currentBoard');
   },
+
+  appIsOffline() {
+    return !Meteor.status().connected;
+  },
 });
 
 Template.header.events({

client/components/main/header.styl

@@ -196,3 +196,15 @@
 
       li
         height: 28px
+
+.offline-warning
+  width: 100%
+  text-align: center
+  padding: 0
+  margin: 0
+  background: #F8ECBD
+  clear: both
+
+  p
+    margin: 7px
+    padding: 0

i18n/en.i18n.json

@@ -51,6 +51,7 @@
     "all-boards": "All boards",
     "and-n-other-card": "And __count__ other card",
     "and-n-other-card_plural": "And __count__ other cards",
+    "app-is-offline": "The application is currently offline, refreshing the page will cause data loss.",
     "archive": "Archive",
     "archive-all": "Archive All",
     "archive-board": "Archive Board",