NCBC-479: Add Retry logic for NMV's

Change-Id: I54cac9aa96a7133aa0dfa34911bef634c05948b1
Reviewed-on: http://review.couchbase.org/39989
Tested-by: Jeffry Morris <jeffrymorris@gmail.com>
Reviewed-by: Mark Nunberg <mnunberg@haskalah.org>