Javadoc8 fixes

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk@1621225 13f79535-47bb-0310-9956-ffa450edef68
Javadoc8 fixes

git-svn-id: https://svn.apache.org/repos/asf/httpcomponents/httpcore/trunk@1621226 13f79535-47bb-0310-9956-ffa450edef68