HDFS-6728. Dynamically add new volumes to DataStorage, formatted if necessary. Contributed by Lei Xu.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1616615 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-10929. Typo in Configuration.getPasswordFromCredentialProviders. Contributed by Larry McCay

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1616616 13f79535-47bb-0310-9956-ffa450edef68
HDFS-6740. Make FSDataset support adding data volumes dynamically. Contributed by Lei Xu.


git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1616623 13f79535-47bb-0310-9956-ffa450edef68
Revert HADOOP-10876.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1616658 13f79535-47bb-0310-9956-ffa450edef68