Add start/stop goals to maven plugin

SpringApplicationLifecycle provides basic lifecycle operations on the
current Spring Boot application (that is checking if the application has
fully started and gracefully terminate the app). It can be registered as
an MBean of the platform MBean server if a specific property is set.

The Maven plugin uses that MBean to check that the application is ready
before ending the "start" phase. It uses it to trigger a proper shutdown
of the application during the "stop" phase.

If the process has to be forked, the platform MBean server is exposed on
a configurable port so that the maven plugin can connect to it.

Such change permits the maven plugin to integrate a classical integration
test scenario where the "start" goal is invoked during the
pre-integration phase and the "stop" goal during the post-integration
phase.

Closes gh-2525

spring-boot-tools/spring-boot-loader-tools/src/main/java/org/springframework/boot/loader/tools/RunProcess.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2014 the original author or authors.
+ * Copyright 2012-2015 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.
@@ -31,6 +31,7 @@ import org.springframework.util.ReflectionUtils;
  * @author Phillip Webb
  * @author Dave Syer
  * @author Andy Wilkinson
+ * @author Stephane Nicoll
  * @since 1.1.0
  */
 public class RunProcess {
@@ -50,11 +51,18 @@ public class RunProcess {
 		this.command = command;
 	}
 
-	public int run(String... args) throws IOException {
-		return run(Arrays.asList(args));
+	public int run(boolean waitForProcess, String... args) throws IOException {
+		return run(waitForProcess, Arrays.asList(args));
 	}
 
-	protected int run(Collection<String> args) throws IOException {
+	/**
+	 * Kill this process.
+	 */
+	public void kill() {
+		doKill();
+	}
+
+	protected int run(boolean waitForProcess, Collection<String> args) throws IOException {
 		ProcessBuilder builder = new ProcessBuilder(this.command);
 		builder.command().addAll(args);
 		builder.redirectErrorStream(true);
@@ -71,17 +79,22 @@ public class RunProcess {
 					handleSigInt();
 				}
 			});
-			try {
-				return process.waitFor();
-			}
-			catch (InterruptedException ex) {
-				Thread.currentThread().interrupt();
-				return 1;
+			if (waitForProcess) {
+				try {
+					return process.waitFor();
+				}
+				catch (InterruptedException ex) {
+					Thread.currentThread().interrupt();
+					return 1;
+				}
 			}
+			return 5;
 		}
 		finally {
-			this.endTime = System.currentTimeMillis();
-			this.process = null;
+			if (waitForProcess) {
+				this.endTime = System.currentTimeMillis();
+				this.process = null;
+			}
 		}
 	}
 
@@ -163,7 +176,11 @@ public class RunProcess {
 		if (hasJustEnded()) {
 			return true;
 		}
+		return doKill();
 
+	}
+
+	private boolean doKill() {
 		// destroy the running process
 		Process process = this.process;
 		if (process != null) {