DATACMNS-1240 - Update copyright years to 2018.

Also, remove some trailing whitespaces and align outdated license header format.

src/test/java/org/springframework/data/authentication/UserCredentialsUnitTests.java

@@ -1,11 +1,11 @@
 /*
- * Copyright 2011-2017 by the original author(s).
+ * Copyright 2011-2018 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,
@@ -21,7 +21,7 @@ import org.junit.Test;
 
 /**
  * Unit tests for {@link UserCredentials}.
- * 
+ *
  * @author Oliver Gierke
  */
 public class UserCredentialsUnitTests {