MorePrivacy: Don't register WHOWAS information

MorePrivacy: Don't register WHOWAS information

Citing an email from Florian to the ngIRCd mailing list:

"I wonder what the expected behaviour is when Conf_MorePrivacy is changed
 from 'yes' to 'no' and the config is reloaded.

 At the moment, WHOWAS will start giving out information on Users that
 were connected during Conf_MorePrivacy=yes period.  If this is not
 wanted, Client_RegisterWhowas() should be changed to not store a record
 when Conf_MorePrivacy is enabled."

And I think it is "not wanted" :-)