QPID-5529: remove failed send from delivery buffer

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1563122 13f79535-47bb-0310-9956-ffa450edef68
QPID-5485: Fixes to broken original checkin
- Fix signatures of dummy windows memory mapped file implementation
- Fix detecting no data dir

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1563152 13f79535-47bb-0310-9956-ffa450edef68
QPID-5527: Upgrade to Jetty 8

Applied patch from Emmanuel Bourg.

git-svn-id: https://svn.apache.org/repos/asf/qpid/trunk@1563153 13f79535-47bb-0310-9956-ffa450edef68
QPID-5485: If no directory for paging file is enabled print warning (as if
memory mapped files were not supported) but still create a queue.
- Also improve DataDir const correctness.