IO-462 IOExceptionWithCause no longer needed

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/io/trunk@1643106 13f79535-47bb-0310-9956-ffa450edef68
IO-462 IOExceptionWithCause no longer needed
Simplify code

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/io/trunk@1643107 13f79535-47bb-0310-9956-ffa450edef68