Better Riak manager handling in vumi_list_messages script tests.
Better Riak manager handling in vumi_list_messages script tests.

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