minor constructor enhancement for usability

Author: richard-jones

src/main/java/org/openarchives/resourcesync/ChangeList.java

@@ -9,6 +9,11 @@ public ChangeList(Date lastMod)
         this(lastMod, null);
     }
 
+    public ChangeList(String capabilityList)
+    {
+        this(null, capabilityList);
+    }
+
     public ChangeList(Date lastMod, String capabilityList)
     {
         super();