Patch for Bug/Enhancement 55818 - add encryption support


git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1553336 13f79535-47bb-0310-9956-ffa450edef68
Fix jdk-differences for encryption patch

git-svn-id: https://svn.apache.org/repos/asf/poi/trunk@1553338 13f79535-47bb-0310-9956-ffa450edef68