Updated release notes

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/io/trunk@1721568 13f79535-47bb-0310-9956-ffa450edef68

Author: krosenvold

RELEASE-NOTES.txt

@@ -20,6 +20,7 @@ New features and bug fixes.
 Changes in this version include:
 
 New features:
+o IO-433:  Converted all testcases to JUnit 4 
 o IO-487:  Add ValidatingObjectInputStream for controlled deserialization 
 o IO-471:  Support for additional encodings in ReversedLinesFileReader Thanks to Leandro Reis. 
 o IO-425:  Setter method for threshold on ThresholdingOutputStream Thanks to Craig Swank.