Delete HeaderFieldsException.java

IPv6 support updated

src/main/java/net/floodlightcontroller/staticflowentry/HeaderFieldsException.java

-package net.floodlightcontroller.staticflowentry;
-
-public class HeaderFieldsException extends Exception {
-
-	/**
-	 * 
-	 */
-	private static final long serialVersionUID = 1L;
-	
-	 public HeaderFieldsException(String s) {
-	      super(s);
-	   }	
-
-}