'tls' and 'ssl' are duplicates of 'starttls' and 'ssltls' and have been deprecated in the upstream modules we use for sending mail notifications. Let's deprecate them as well and issue a warning when they are still used. Fixes: #7345
Signed-off-by: jkoberg <jkoberg@owncloud.com>
Signed-off-by: Christian Richter <crichter@owncloud.com>