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/tx.groovy

@@ -0,0 +1,17 @@
+package org.test
+
+@Grab("hsqldb")
+
+@Configuration
+@EnableTransactionManagement
+class Example implements CommandLineRunner {
+
+	@Autowired
+	JdbcTemplate jdbcTemplate
+
+	@Transactional
+	void run(String... args) {
+		println "Foo count=" + jdbcTemplate.queryForObject("SELECT COUNT(*) from FOO", Integer)
+	}
+}
+