Add support for notifications of new server or plugins updates
. Let admins receive notifications of new updates (server or plugins)
. Let admins disable the check for update service
. Let admins disable the notification of new updates
. Change the main page of the admin console to alert admins when a new release is available
. Change the plugins page to show when a new version is available
. Add a new page to show available plugins to download and install
By default check for updates every 48 hours. Let admins change the frequency.