CHANGES.txt: move HADOOP-10404 underneath branch 2.6
HADOOP-10809. hadoop-azure: page blob support. Contributed by Dexter Bradshaw, Mostafa Elhemali, Eric Hanson, and Mike Liddell.
HADOOP-11179. Java untar should handle the case that the file entry comes without its parent directory entry. Contributed by Craig Welch.
YARN-2598 GHS should show N/A instead of null for the inaccessible information  (Zhijie Shen via mayank)
HDFS-7202. Should be able to omit package name of SpanReceiver on "hadoop trace -add" (iwasakims via cmccabe)
HADOOP-11161. Expose close method in KeyProvider to give clients of Provider implementations a hook to release resources. Contribued by Arun Suresh.
HADOOP-11133. Should trim the content of keystore password file for JavaKeyStoreProvider (Yi Liu via umamahesh)
HDFS-7217. Better batching of IBRs. Contributed by Kihwal Lee.
HADOOP-11175. Fix several issues of hadoop security configuration in user doc. Contributed by Yi Liu.
YARN-2493. Added user-APIs for using node-labels. Contributed by Wangda Tan.
HDFS-7195. Update user doc of secure mode about Datanodes don't require root or jsvc. Contributed by Chris Nauroth.
HADOOP-11178. Fix findbugs exclude file. (Arun Suresh via wang)
YARN-2629. Made the distributed shell use the domain-based timeline ACLs. Contributed by Zhijie Shen.
HADOOP-11174. Delegation token for KMS should only be got once if it already exists. (Yi Liu via wang)
YARN-2544. Added admin-API objects for using node-labels. Contributed by Wangda Tan.
HADOOP-11184. Update Hadoop's lz4 to r123 (cmccabe)
YARN-2180. [YARN-1492] In-memory backing store for cache manager. (Chris Trezzo via kasha)
YARN-2617. Fixed ApplicationSubmissionContext to still set resource for backward compatibility. Contributed by Wangda Tan.
HDFS-7026. Introduce a string constant for "Failed to obtain user group info...". Contributed by Yongjun Zhang.
YARN-2671. Fix the Jira number in the change log.