HADOOP-10562. Namenode exits on exception without printing stack trace in AbstractDelegationTokenSecretManager. (Contributed by Suresh Srinivas)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1592002 13f79535-47bb-0310-9956-ffa450edef68
HADOOP-10549. MAX_SUBST and varPat should be final in Configuration.java. Contributed by Gera Shegalov.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/trunk@1592011 13f79535-47bb-0310-9956-ffa450edef68