Fixing CHANGES.txt before release

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.0.4-alpha@1486272 13f79535-47bb-0310-9956-ffa450edef68
Updating releasenotes.html for 2.0.4.1 release

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.0.4-alpha@1486273 13f79535-47bb-0310-9956-ffa450edef68