INT-741 🎉 persisting last known version to localstorage

This is for future updates that want to know what version the user has used before.

E.g. feature tour only shows new features, internal data structure schemas might change and need migration, etc.

Author: rueckstiess

src/app.js

@@ -259,7 +259,6 @@ app.extend({
    *
    * @param {String} id - A key in `FEATURES`.
    * @param {Boolean} bool - whether to enable (true) or disable (false)
-   * @return {Boolean}
    */
   setFeature: function(id, bool) {
     FEATURES[id] = bool;

src/home/index.js

@@ -51,9 +51,10 @@ var HomeView = View.extend({
   },
   render: function() {
     this.renderWithTemplate(this);
-    if (_.isUndefined(localStorage.tourHasRun)) {
+    if (_.isUndefined(localStorage.lastKnownVersion)
+      || localStorage.lastKnownVersion !== app.meta['App Version']) {
       this.renderSubview(new TourView(), this.queryByHook('tour-container'));
-      localStorage.tourHasRun = 'true';
+      localStorage.lastKnownVersion = app.meta['App Version'];
     }
   },
   onInstanceFetched: function() {