mod_auth_ccert/README: Add certificate purpose conifg to example Thanks debacle By default Prosody validates all client certificates as if they were server certificates, for historical reasons, from a time when you couldn't get certificates with the client purpose.

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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.