Migrate existing tests from deprecated package

Update the existing tests to use the relocated `spring-boot-test`
classes. Restructuring was achieved using the following command:

find . -type f -name '*.java' -exec sed -i '' \
-e s/org.springframework.boot.test.ConfigFileApplicationContextInitializer/\
org.springframework.boot.test.context.ConfigFileApplicationContextInitializer/g \
-e s/org.springframework.boot.test.EnvironmentTestUtils/\
org.springframework.boot.test.util.EnvironmentTestUtils/g \
-e s/org.springframework.boot.test.IntegrationTest/\
org.springframework.boot.test.context.IntegrationTest/g \
-e s/org.springframework.boot.test.IntegrationTestPropertiesListener/\
org.springframework.boot.test.context.IntegrationTestPropertiesListener/g \
-e s/org.springframework.boot.test.OutputCapture/\
org.springframework.boot.test.rule.OutputCapture/g \
-e s/org.springframework.boot.test.SpringApplicationConfiguration/\
org.springframework.boot.test.context.SpringApplicationConfiguration/g \
-e s/org.springframework.boot.test.SpringApplicationContextLoader/\
org.springframework.boot.test.context.SpringApplicationContextLoader/g \
-e s/org.springframework.boot.test.SpringBootMockServletContext/\
org.springframework.boot.test.mock.web.SpringBootMockServletContext/g \
-e s/org.springframework.boot.test.TestRestTemplate/\
org.springframework.boot.test.web.client.TestRestTemplate/g \
-e s/org.springframework.boot.test.WebIntegrationTest/\
org.springframework.boot.test.context.web.WebIntegrationTest/g {} \;

See gh-5293

spring-boot-samples/spring-boot-sample-logback/src/test/java/sample/logback/SampleLogbackApplicationTests.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2014 the original author or authors.
+ * Copyright 2012-2016 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.
@@ -19,7 +19,7 @@ package sample.logback;
 import org.junit.Rule;
 import org.junit.Test;
 
-import org.springframework.boot.test.OutputCapture;
+import org.springframework.boot.test.rule.OutputCapture;
 
 import static org.hamcrest.Matchers.containsString;
 import static org.hamcrest.Matchers.not;