Return ';'-delimited hostlist (was None)

Change-Id: I8ff568c10e45c957d02fde44daf7d8b115557deb
Reviewed-on: http://review.couchbase.org/26626
Reviewed-by: Matt Ingenthron <matt@couchbase.com>
Tested-by: Mordechai Nunberg <mnunberg@haskalah.org>