Fix scope on two titan-cassandra test dependencies
Fix scope on two titan-cassandra test dependencies

titan-cassandra's dependencies on randomizedtesting-runner and
junit-benchmarks should both be declared with <scope>test</scope>

mbrukman/titan,pluradj/titan,englishtown/titan,amcp/titan,amcp/titan,mbrukman/titan,englishtown/titan,CYPP/titan,graben1437/titan,graben1437/titan,dylanht/titan,pluradj/titan,CYPP/titan,thinkaurelius/titan,amcp/titan,graben1437/titan,thinkaurelius/titan,graben1437/titan,mbrukman/titan,amcp/titan,dylanht/titan,englishtown/titan,pluradj/titan,dylanht/titan,CYPP/titan,dylanht/titan,thinkaurelius/titan,englishtown/titan,mbrukman/titan,thinkaurelius/titan,mbrukman/titan,pluradj/titan,CYPP/titan