Add basic integration test to samples

spring-cloud-sleuth-samples/spring-cloud-sleuth-sample/src/test/java/sample/SampleSleuthApplicationTests.java

@@ -0,0 +1,18 @@
+package sample;
+
+import org.junit.Test;
+import org.junit.runner.RunWith;
+import org.springframework.boot.test.SpringApplicationConfiguration;
+import org.springframework.test.context.junit4.SpringJUnit4ClassRunner;
+import org.springframework.test.context.web.WebAppConfiguration;
+
+@RunWith(SpringJUnit4ClassRunner.class)
+@SpringApplicationConfiguration(classes = SampleSleuthApplication.class)
+@WebAppConfiguration
+public class SampleSleuthApplicationTests {
+
+	@Test
+	public void contextLoads() {
+	}
+
+}