HDFS-6509. Create a special /.reserved/raw directory for raw access to encrypted data. Contributed by Charles Lamb.

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/fs-encryption@1614490 13f79535-47bb-0310-9956-ffa450edef68
HDFS-6509 addendum, extra file

git-svn-id: https://svn.apache.org/repos/asf/hadoop/common/branches/fs-encryption@1614491 13f79535-47bb-0310-9956-ffa450edef68