added comment

Author: raydac

src/main/java/com/igormaznitsa/prologparser/exceptions/CriticalUnexpectedError.java

@@ -23,6 +23,7 @@
 
 /**
  * Unexpected error breaks functionality of the library.
+ * <b>If you meet such exception then contact developer!</b>
  */
 public class CriticalUnexpectedError extends Error {
   private static final long serialVersionUID = -8219655356191420973L;