code: public XMLWriter value(ByteBuffer b) {
          append(escapeXMLEntities(Base64.encodeAsString(BinaryUtils.copyBytesFrom(b))));
          return this;
      }
docs: Adds the specified value as Base64 encoded text to the current position of the in
  progress XML document.
  
  @param b
  The binary data to add to the XML document.
  
  @return This XMLWriter so that additional method calls can be chained
  together.