UIMA-3777 Agent should not change process exit code (and WebServer should NOT suppress display of exit code when Reason Scheduler is Voluntary or Forced or Stopped)

git-svn-id: https://svn.apache.org/repos/asf/uima/sandbox/uima-ducc/trunk@1591396 13f79535-47bb-0310-9956-ffa450edef68