HDFS-5488. Clean up TestHftpURLTimeout. Contributed by Haohui Mai.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1540894 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5495. Remove further JUnit3 usages from HDFS. Contributed by Jarek Jarcec Cecho.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1540914 13f79535-47bb-0310-9956-ffa450edef68
Move HDFS-5495 to 2.3.0 in CHANGES.txt

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1540917 13f79535-47bb-0310-9956-ffa450edef68
MAPREDUCE-1176. FixedLengthInputFormat and FixedLengthRecordReader (Mariappan Asokan and BitsOfInfo via Sandy Ryza)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1540931 13f79535-47bb-0310-9956-ffa450edef68
YARN-1400. yarn.cmd uses HADOOP_RESOURCEMANAGER_OPTS. Should be YARN_RESOURCEMANAGER_OPTS. Contributed by Raja Aluri.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1540938 13f79535-47bb-0310-9956-ffa450edef68
HDFS-5425. Renaming underconstruction file with snapshots can make NN failure on restart. Contributed by Vinay and Jing Zhao.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1541261 13f79535-47bb-0310-9956-ffa450edef68
Merge remote-tracking branch: upstream/trunk