Fix handling of Web calendars

- handle Web calendars that require authentication;
- properly save the "reload on login" option;
- reload Web calendars when clicking on the reload button on top of the
  events/tasks list;
- properly activate the checkbox of new calendars (as they are enabled
  by default).

Fixes #3326

UI/WebServerResources/js/Scheduler/CalendarListController.js

@@ -309,7 +309,9 @@
     }
 
     function reload() {
-      $rootScope.$emit('calendars:list');
+      Calendar.reloadWebCalendars().finally(function() {
+        $rootScope.$emit('calendars:list');
+      });
     }
 
     function cancelSearch() {