Add comment indicating CHUNK_SEPARTOR variable may be private in future versions

git-svn-id: https://svn.apache.org/repos/asf/commons/proper/codec/trunk@801706 13f79535-47bb-0310-9956-ffa450edef68

Author: Niall Kegan Pemberton

src/java/org/apache/commons/codec/binary/Base64.java

@@ -69,6 +69,10 @@ public class Base64 implements BinaryEncoder, BinaryDecoder {
 
     /**
      * Chunk separator per RFC 2045 section 2.1.
+     *
+     * <p>
+     * N.B. The next major release may break compatibility and make this field private.
+     * </p>
      * 
      * @see <a href="http://www.ietf.org/rfc/rfc2045.txt">RFC 2045 section 2.1</a>
      */