Relocate projects to spring-boot-project

Move projects to better reflect the way that Spring Boot is released.

The following projects are under `spring-boot-project`:

  - `spring-boot`
  - `spring-boot-autoconfigure`
  - `spring-boot-tools`
  - `spring-boot-starters`
  - `spring-boot-actuator`
  - `spring-boot-actuator-autoconfigure`
  - `spring-boot-test`
  - `spring-boot-test-autoconfigure`
  - `spring-boot-devtools`
  - `spring-boot-cli`
  - `spring-boot-docs`

See gh-9316

spring-boot-project/spring-boot-cli/samples/rabbit.groovy

@@ -0,0 +1,32 @@
+package org.test
+
+import java.util.concurrent.CountDownLatch
+
+@Log
+@Configuration
+@EnableRabbit
+class RabbitExample implements CommandLineRunner {
+
+	private CountDownLatch latch = new CountDownLatch(1)
+
+	@Autowired
+	RabbitTemplate rabbitTemplate
+
+	void run(String... args) {
+		log.info "Sending RabbitMQ message..."
+		rabbitTemplate.convertAndSend("spring-boot", "Greetings from Spring Boot via RabbitMQ")
+		latch.await()
+	}
+
+	@RabbitListener(queues = 'spring-boot')
+	def receive(String message) {
+		log.info "Received ${message}"
+		latch.countDown()
+	}
+
+	@Bean
+	Queue queue() {
+		new Queue("spring-boot", false)
+	}
+
+}