mod_turn_external: Fix type of config option (thanks mirux) There was a separate boolean option to enable TLS before, but it was merged with the port number option and it seems the typed API interface got confused. Backport of trunk rev aa7a8aa64d3f

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summary: Log a message once per minute
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This module sends `-- MARK --` to the log once per minute. This may be
useful to give a sense of how busy the server is or see that logging and
timers are still working.