calendar: fix url for fedocal in apps and redirect for old calendars
    
    fedocal moved to calendar.fedoraproject.org, so use that in apps.
    Also some links to the old admin.fedoraproject.org/calendar/whatever
    still exist, so redirect those to calendar.fedoraproject.org/whatever
    
    Fixes ticket 10616
    
    Signed-off-by: Kevin Fenzi <kevin@scrye.com>