HDFS-7119: update error messages
HDFS-7119: correct permission manipulation on testFailToDelete
HDFS-7119: correct permission manipulation on testFailToDelete again
HDFS-7119: try removing execute permissions
HDFS-7119: another attempt at blocking delete
HDFS-7119: fix compilation error
HDFS-7119: change ordering of chmod statement
HDFS-7119: temporary debugging output
HDFS-7119: rechecking existence
HDFS-7119: giving up on a delete test and cleaning up
HDFS-7119: use native rename
HDFS-7119: remove unnecessary rename