Merge pull request #228 from mar-kolya/parameter-exception-description-and-cause

Allow users to create ParameterException with description and cause
diff --git a/src/main/java/com/beust/jcommander/ParameterException.java b/src/main/java/com/beust/jcommander/ParameterException.java
index 3c0f588..2bba7d1 100644
--- a/src/main/java/com/beust/jcommander/ParameterException.java
+++ b/src/main/java/com/beust/jcommander/ParameterException.java
@@ -34,5 +34,9 @@
   public ParameterException(String string) {
     super(string);
   }
+  
+  public ParameterException(String string, Throwable t) {
+      super(string, t);
+  }   
 
 }