Attempt a fix at #612 by returning a copy of the list of filters in the sub query to avoid hash issues.
Attempt a fix at #612 by returning a copy of the list of filters
in the sub query to avoid hash issues.

Signed-off-by: Chris Larsen <83037b211e1d109d6858769a113e269c3139ffd3@yahoo-inc.com>

OpenTSDB/opentsdb,OpenTSDB/opentsdb,MadDogTechnology/opentsdb,OpenTSDB/opentsdb,MadDogTechnology/opentsdb,alienth/opentsdb,eswdd/opentsdb,eswdd/opentsdb,alienth/opentsdb,MadDogTechnology/opentsdb