ACCUMULO-1320 added a note about commons-io; users do not need to make the local wal directory if it doesn't exist

git-svn-id: https://svn.apache.org/repos/asf/accumulo/branches/1.5@1480290 13f79535-47bb-0310-9956-ffa450edef68
ACCUMULO-1320 added a note about commons-io; users do not need to make the local wal directory if it doesn't exist

git-svn-id: https://svn.apache.org/repos/asf/accumulo/trunk@1480291 13f79535-47bb-0310-9956-ffa450edef68