Applying github pull request https://github.com/apache/commons-lang/pull/5, linked as LANG-928, fixing a bug in OctalEscaper trying to parse octal numbers longer than 3 digits

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/lang/trunk@1535911 13f79535-47bb-0310-9956-ffa450edef68