HDFS-4776. Backport SecondaryNameNode web ui.


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MAPREDUCE-5198. Fix a race condition during TaskTracker re-init which was causing failures since task directories were being cleaned up in multiple threads. Contributed by Arpit Gupta.

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MAPREDUCE-5154. Ensure job delegation token renewal is cancelled after job staging directory is deleted. Contributed by Sandy Ryza & Arun C. Murthy.

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MAPREDUCE-5202. Revert MAPREDUCE-4397 to improve LinuxTaskController security. (omalley)


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HADOOP-9537. Backport changes to add support running Hadoop client on AIX. Backported by Arpit Agarwal.

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HADOOP-8711. Provide an option for IPC server users to avoid printing stack information for certain exceptions. Contributed by Brandon Li.

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HADOOP-8711. Add a missing file in previous commit r1478426

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HDFS-3817. Avoid printing stack information for SafeModeException. Contributed by Brandon Li.

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HDFS-4774. Backport HDFS-4525: Provide an API for knowing whether a file is closed.  Contributed by Ted Yu


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HADOOP-9543. TestFsShellReturnCode may fail if the hardcoded user "admin" is not a valid user in the loacl OS.


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