Confomon: Filter out CONNECT_ERROR or NETWORK_ERROR

This is where we get bootstrap information from. If this returns a
CONNECT_ERROR, we clobber any real error received. The CONNECT_ERROR is
an artificial error thrown by various providers when no more hosts
remain.

Change-Id: Iafb536e4b7c1d63af2ff876a33d08e184d7e1547
Reviewed-on: http://review.couchbase.org/44290
Tested-by: Mark Nunberg <mnunberg@haskalah.org>
Reviewed-by: Sergey Avseyev <sergey.avseyev@gmail.com>