Move HDFS-4366 to 2.8.0 in CHANGES.txt
Move HDFS-4366 to 2.8.0 in CHANGES.txt

zjshen/hadoop-YARN-2928-POC,zjshen/hadoop-YARN-2928-POC,zjshen/hadoop-YARN-2928-POC,zjshen/hadoop-YARN-2928-POC,zjshen/hadoop-YARN-2928-POC,zjshen/hadoop-YARN-2928-POC,zjshen/hadoop-YARN-2928-POC