MB-16513: Collect only the specified stat from all nodes.
MB-16513: Collect only the specified stat from all nodes.

Change-Id: Id5577185c0a6be7030140df17e3af987aa37f9b1
Reviewed-on: http://review.couchbase.org/56304
Tested-by: Poonam D <6855f09986fe28ed7e8cdd9d60db878d898703d5@couchbase.com>
Reviewed-by: Artem Stemkovski <15a0730a27c69f62ab86f2b6c639fca202166c02@couchbase.com>

membase/ns_server,membase/ns_server,ceejatec/ns_server,ceejatec/ns_server,membase/ns_server,ceejatec/ns_server,membase/ns_server,ceejatec/ns_server,ceejatec/ns_server,membase/ns_server,membase/ns_server,ceejatec/ns_server