restructured and updated CHANGES.txt to contain all changes in the 0.6 release

git-svn-id: https://svn.apache.org/repos/asf/incubator/odf/trunk@1431194 13f79535-47bb-0310-9956-ffa450edef68
Update the CHANGES.txt for Release 0.6 incubating base on Florian Hopf's update

git-svn-id: https://svn.apache.org/repos/asf/incubator/odf/trunk@1431197 13f79535-47bb-0310-9956-ffa450edef68
Add Dali Liu's key information

git-svn-id: https://svn.apache.org/repos/asf/incubator/odf/trunk@1431198 13f79535-47bb-0310-9956-ffa450edef68
prepare 0.6 RC1

git-svn-id: https://svn.apache.org/repos/asf/incubator/odf/trunk@1431222 13f79535-47bb-0310-9956-ffa450edef68
prepare for 0.6-incubating RC1

git-svn-id: https://svn.apache.org/repos/asf/incubator/odf/trunk@1431231 13f79535-47bb-0310-9956-ffa450edef68