CLI Integration Sample Shutdown

Fixes gh-761

Also add some sugar to the println so that it stands
out a little against the logging.

spring-boot-cli/samples/integration.groovy

@@ -4,6 +4,9 @@ package org.test
 @EnableIntegration
 class SpringIntegrationExample implements CommandLineRunner {
 
+	@Autowired
+	private ApplicationContext context;
+
 	@Bean
 	DirectChannel input() {
 		new DirectChannel();
@@ -11,7 +14,17 @@ class SpringIntegrationExample implements CommandLineRunner {
 
 	@Override
 	void run(String... args) {
-		println new MessagingTemplate(input()).convertSendAndReceive("World", String)
+		println()
+		println '>>>> ' + new MessagingTemplate(input()).convertSendAndReceive("World", String) + ' <<<<'
+		println()
+		/*
+		 *  Since this is a simple application that we want to exit right away,
+		 *  close the context. For an active integration application, with pollers
+		 *  etc, you can either suspend the main thread here (e.g. with System.in.read()),
+		 *  or exit the run() method without closing he context, and stop the
+		 *  application later using some other technique (kill, JMX etc).
+		 */
+		context.close()
 	}
 }