Bumped up compile warnings

Bumped up the compiler warning to errors.

spring-ws-test/src/main/java/org/springframework/ws/test/support/SourceAssertionError.java

@@ -1,11 +1,11 @@
 /*
- * Copyright 2005-2011 the original author or authors.
+ * Copyright 2005-2014 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
  * You may obtain a copy of the License at
  *
- *     http://www.apache.org/licenses/LICENSE-2.0
+ *      http://www.apache.org/licenses/LICENSE-2.0
  *
  * Unless required by applicable law or agreed to in writing, software
  * distributed under the License is distributed on an "AS IS" BASIS,
@@ -32,6 +32,7 @@ import org.springframework.xml.transform.TransformerHelper;
  * @author Arjen Poutsma
  * @since 2.0.1 
  */
+@SuppressWarnings("serial")
 public class SourceAssertionError extends AssertionError {
 
     private final String sourceLabel;