Update index page

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1496699 13f79535-47bb-0310-9956-ffa450edef68
Update CHANGES.txt

git-svn-id: https://svn.apache.org/repos/asf/hama/trunk@1496700 13f79535-47bb-0310-9956-ffa450edef68
Merge remote-tracking branch 'upstream/trunk' into vectormatrix