Make sure all ConnHandlers have a Connection object

This will allow us to be able to set the logHeader() function to
allow us to better categorize upr and tap log messages.

Change-Id: Ib61cc3f388fc536d5a4f6739e89bca7a286a200d
Reviewed-on: http://review.couchbase.org/32824
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Tested-by: Michael Wiederhold <mike@couchbase.com>