Using only major version in docs metadata

otherwise Google is confused how to find docs for a given v. of Cayenne

git-svn-id: https://svn.apache.org/repos/asf/cayenne/main/trunk@1555527 13f79535-47bb-0310-9956-ffa450edef68
updating copyright year

git-svn-id: https://svn.apache.org/repos/asf/cayenne/main/trunk@1555528 13f79535-47bb-0310-9956-ffa450edef68