fix for date sorting

angular_app/events-list.html

@@ -19,8 +19,8 @@
                     <select id="events-order" class="form-control" ng-model="eventsOrderProp">
                         <option value="title">{{'Title' | translate}}</option>
                         <option value="-title">{{'Title (descending)' | translate}}</option>
-                        <option value="begin-date">{{'Date' | translate}}</option>
-                        <option value="-begin-date">{{'Date (descending)' | translate}}</option>
+                        <option value="'begin-date'">{{'Date' | translate}}</option>
+                        <option value="'-begin-date'">{{'Date (descending)' | translate}}</option>
                     </select>
                 </div>
             </form>

angular_app/js/controllers.js

@@ -42,7 +42,7 @@ eventManControllers.controller('EventsListCtrl', ['$scope', 'Event',
     function ($scope, Event) {
         $scope.events = Event.all();
         $scope.personsOrderProp = 'name';
-        $scope.eventsOrderProp = '-begin-date';
+        $scope.eventsOrderProp = "'-begin-date'";
 
         $scope.remove = function(_id) {
             Event.remove({'id': _id}, function() {