ADOOP-9643. org.apache.hadoop.security.SecurityUtil calls toUpperCase(Locale.getDefault()) as well as toLowerCase(Locale.getDefault()) on hadoop.security.authentication value. (markrmiller@gmail.com via tucu)

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.1-beta@1504967 13f79535-47bb-0310-9956-ffa450edef68
merge -c 1504971 from branch-2 to branch-2.1-beta to YARN-919. Document setting default heap sizes in yarn env.sh Contributed by Mayank Bansal.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/branch-2.1-beta@1504972 13f79535-47bb-0310-9956-ffa450edef68