MB-10881 expose upragg stats in UI

first version of stats UI for further refinement by PM

Change-Id: I2ea61ed659c6272744dcd6c1b466f94fc24b9b18
Reviewed-on: http://review.couchbase.org/37405
Tested-by: Artem Stemkovski <artem@couchbase.com>
Reviewed-by: Aliaksey Kandratsenka <alkondratenko@gmail.com>