Randomize bootstrap nodes

For some reason this was never re-implemented

Change-Id: I6a36edf8e327d6efd0ab4f561dfb1d0b6be691dd
Reviewed-on: http://review.couchbase.org/34018
Reviewed-by: Brett Lawson <brett19@gmail.com>
Tested-by: Mark Nunberg <mnunberg@haskalah.org>