Added unit tests to cover missing data responses from map/reduce jobs
Added unit tests to cover missing data responses from map/reduce jobs

SiftLogic/riak-erlang-client,GabrielNicolasAvellaneda/riak-erlang-client,linearregression/riak-erlang-client,paulperegud/riak-erlang-client,jmayfield74/riak-erlang-client,groovenauts-erlang/riak-erlang-client,rhumbertgz/riak-erlang-client,inaka/riak-erlang-client,esl/riak-erlang-client,pma/riak-erlang-client