Updated project web site or HttpCore 4.2.4 release

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpcore/branches/4.2.x@1458305 13f79535-47bb-0310-9956-ffa450edef68
Updated HttpCore 4.2.4 release notes

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpcore/branches/4.2.x@1458306 13f79535-47bb-0310-9956-ffa450edef68