CBQE-0: add support to load data to active_resident_ratio

Change-Id: Ibea83b88d80ff18325966b0b9d79591b8237825f
Reviewed-on: http://review.couchbase.org/37033
Reviewed-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>
Tested-by: Sangharsh Agarwal <sangharsh.agarwal@globallogic.com>