## Description
Implement TLS/SSL encryption for sending emails via SMTP. When an SMTP
provider explicitly requires TLS/SSL communication the current
implementation runs in a timeout and fails. A new configuration
parameter for smtp was added to enable TLS/SSL communication.
This would solve #5958
## Tests
I built a local docker image of my branch. The email provider I was
using is mailbox.org and using the tls configuration. Registering a new
user then resulted in a sent email containing the verification code.
I did not test a setup without TLS/SSL.
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