Convert remaining samples to use random port

Partial fix for gh-337. See also gh-607 which complements this, but might
conflict on a merge.

spring-boot-samples/spring-boot-sample-actuator-log4j/src/test/java/sample/actuator/log4j/SampleActuatorApplicationTests.java

@@ -20,6 +20,7 @@ import java.util.Map;
 
 import org.junit.Test;
 import org.junit.runner.RunWith;
+import org.springframework.beans.factory.annotation.Value;
 import org.springframework.boot.test.IntegrationTest;
 import org.springframework.boot.test.TestRestTemplate;
 import org.springframework.boot.test.SpringApplicationConfiguration;
@@ -39,15 +40,18 @@ import static org.junit.Assert.assertEquals;
 @RunWith(SpringJUnit4ClassRunner.class)
 @SpringApplicationConfiguration(classes = SampleActuatorApplication.class)
 @WebAppConfiguration
-@IntegrationTest
+@IntegrationTest("server.port=0")
 @DirtiesContext
 public class SampleActuatorApplicationTests {
 
+	@Value("${local.server.port}")
+	private int port;
+
 	@Test
 	public void testHome() throws Exception {
 		@SuppressWarnings("rawtypes")
 		ResponseEntity<Map> entity = new TestRestTemplate().getForEntity(
-				"http://localhost:8080", Map.class);
+				"http://localhost:" + port, Map.class);
 		assertEquals(HttpStatus.OK, entity.getStatusCode());
 		@SuppressWarnings("unchecked")
 		Map<String, Object> body = entity.getBody();