Upgraded HttpClient dependency to version 4.3.2 (caching module is still at 4.3.1 due to HTTPCLIENT-1450)

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpasyncclient/trunk@1561684 13f79535-47bb-0310-9956-ffa450edef68
HTTPASYNC-64: race conditions in async caching module

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpasyncclient/trunk@1561685 13f79535-47bb-0310-9956-ffa450edef68
HTTPASYNC-64: race conditions in async caching module (release notes)

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpasyncclient/trunk@1561694 13f79535-47bb-0310-9956-ffa450edef68
 Persistent connections always get discarded in case of a response future cancellation even if they can be kept alive

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpasyncclient/trunk@1562788 13f79535-47bb-0310-9956-ffa450edef68
Additional debug logs

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpasyncclient/trunk@1563093 13f79535-47bb-0310-9956-ffa450edef68
HTTPASYNC-68: Connection closed by the opposite endpoint immediately upon its lease from the pool is never released back and reclaimed by the pool (collection leak)
Contributed by Dmitry Potapov <potapov.d at gmail.com>

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpasyncclient/trunk@1567748 13f79535-47bb-0310-9956-ffa450edef68
Upgraded HttpCore to version 4.3.2

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpasyncclient/trunk@1568819 13f79535-47bb-0310-9956-ffa450edef68
Conflicts
HTTPASYNC-69: premature cancellation of response consumer to immediately shut down and release the underlying connection