HADOOP-10322. Add ability to read principal names from a keytab. Contributed by Benoy Antony and Daryn Sharp.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1590637 13f79535-47bb-0310-9956-ffa450edef68
HDFS-6218. Audit log should use true client IP for proxied webhdfs operations. Contributed by Daryn Sharp.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1590640 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-5812. Make job context available to OutputCommitter.isRecoverySupported(). Contributed by Mohammad Kamrul Islam


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1590668 13f79535-47bb-0310-9956-ffa450edef68
HDFS-6288. DFSInputStream Pread doesn't update ReadStatistics. Contributed by Juan Yu.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1590776 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-10508. RefreshCallQueue fails when authorization is enabled. Contributed by Chris Li.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1590876 13f79535-47bb-0310-9956-ffa450edef68
Merge branch 'trunk' into HDFS-5168