COMPRESS-266 document changes

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/compress/trunk@1571660 13f79535-47bb-0310-9956-ffa450edef68
what's coming teaser

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/compress/trunk@1571661 13f79535-47bb-0310-9956-ffa450edef68