Add benchmark for vumi persistence layer.
Add benchmark for vumi persistence layer.

TouK/vumi,vishwaprakashmishra/xmatrix,TouK/vumi,harrissoerja/vumi,harrissoerja/vumi,vishwaprakashmishra/xmatrix,harrissoerja/vumi,TouK/vumi,vishwaprakashmishra/xmatrix