SLING-2945 related : ClusterLoadTest discovered another race condition where during a vote.matches the vote is deleted. Handling this situation properly now

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1499993 13f79535-47bb-0310-9956-ffa450edef68
SLING-2945 : slowing down test to have it run on jenkins/travis properly

git-svn-id: https://svn.apache.org/repos/asf/sling/trunk@1500014 13f79535-47bb-0310-9956-ffa450edef68
travis experiment
run, travis, run
travis: disable notifications since this is a personal testbed
travis: run against multiple runtimes