Get rid of unused import warnings

Author: dhendriks

src/main/java/com/github/javabdd/BDDVarSet.java

@@ -3,7 +3,7 @@
 // Licensed under the terms of the GNU LGPL; see COPYING for details.
 package com.github.javabdd;
 
-import java.util.Arrays;
+//import java.util.Arrays;
 
 /**
  * <p>Some BDD methods, namely <tt>exist()</tt>, <tt>forall()</tt>, <tt>unique()</tt>,