QPID-6125 : make coalescing committer commit on stop if environment still viable

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1633671 13f79535-47bb-0310-9956-ffa450edef68
QPID-6174 : Increase defaults for Jetty thread pool size

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1633672 13f79535-47bb-0310-9956-ffa450edef68