Fixed synchronization bug

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk@1464365 13f79535-47bb-0310-9956-ffa450edef68
Moved DateUtils to o.a.http.client.utils

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk@1464366 13f79535-47bb-0310-9956-ffa450edef68
Removed Clirr plugin config from HttpClient Cache (should be inherited from parent)

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpclient/trunk@1464368 13f79535-47bb-0310-9956-ffa450edef68