correct locations of some items in CHANGES.txt from 1.2.0 to 1.1.2

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1@1454891 13f79535-47bb-0310-9956-ffa450edef68
Preparing for 1.3.0 development on branch-1

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-1@1454902 13f79535-47bb-0310-9956-ffa450edef68