MB-10135 added UPR_ADD_STREAM_DISKONLY flag

Change-Id: I8f6812a80a50c8336cba9239acfded0642885816
Reviewed-on: http://review.couchbase.org/33414
Reviewed-by: Michael Wiederhold <mike@couchbase.com>
Reviewed-by: Trond Norbye <trond.norbye@gmail.com>
Tested-by: Michael Wiederhold <mike@couchbase.com>