mod_sasl2_bind2, mod_sasl2_sm: Remove bind2 <features/> wrapper element
This was dropped from the spec. It's more consistent with SASL2.
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summary: Log a message once per minute
...
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.