CBQE:0 upr_snapshot_seq has been removed from checkpoint record, removing that and other unused fields

Change-Id: I72e7aa764549853e2ec84710d74ce4cd958ebaec
Reviewed-on: http://review.couchbase.org/39817
Reviewed-by: Aruna Piravi <aruna@couchbase.com>
Tested-by: Aruna Piravi <aruna@couchbase.com>