Convert remaining samples to use random port

Partial fix for gh-337. See also gh-607 which complements this, but might
conflict on a merge.

spring-boot-docs/src/main/asciidoc/howto.adoc

@@ -364,30 +364,23 @@ that and be sure that it has initialized is to add a `@Bean` of type
 `ApplicationListener<EmbeddedServletContainerInitializedEvent>` and pull the container
 out of the event when it is published.
 
-A really useful thing to do in is to autowire the `EmbeddedWebApplicationContext` into a
-test case and use it to discover the port that the app is running on. In that way you can
-use a test profile that chooses a random port (`server.port=0`) and make your test suite
-independent of its environment. Example:
+A really useful thing to do in is to use `@IntegrationTest` to set `server.port=0`
+and then inject the actual ("local") port as a `@Value`. Example:
 
 [source,java,indent=0,subs="verbatim,quotes,attributes"]
 ----
 	@RunWith(SpringJUnit4ClassRunner.class)
 	@SpringApplicationConfiguration(classes = SampleDataJpaApplication.class)
 	@WebApplication
-	@IntegrationTest
-	@ActiveProfiles("test")
+	@IntegrationTest("server.port:0")
 	public class CityRepositoryIntegrationTests {
 
 		@Autowired
 		EmbeddedWebApplicationContext server;
-
+        
+        @Value("${local.server.port}")
 		int port;
 
-		@Before
-		public void init() {
-			port = server.getEmbeddedServletContainer().getPort();
-		}
-
 		// ...
 
 	}

spring-boot-docs/src/main/asciidoc/spring-boot-features.adoc

@@ -199,6 +199,7 @@ sensible overriding of values, properties are considered in the the following or
 . Command line arguments.
 . Java System properties (`System.getProperties()`).
 . OS environment variables.
+. A `RandomValueProperySource` that only has properties in `random.*`.
 . `@PropertySource` annotations on your `@Configuration` classes.
 . Application properties outside of your packaged jar (`application.properties`
   including YAML and profile variants).
@@ -230,8 +231,25 @@ default `name`. When running in production, an `application.properties` can be p
 outside of your jar that overrides `name`; and for one-off testing, you can launch with
 a specific command line switch (e.g. `java -jar app.jar --name="Spring"`).
 
+The `RandomValueProperySource` is useful for injecting random values
+(e.g. into secrets or test cases). It can produce integers, longs or
+strings, e.g.
 
 
+[source,properties,indent=0]
+----
+my.secret=${random.value}
+my.number=${random.int}
+my.bignumber=${random.long}
+my.number.less.than.ten=${random.int(10)}
+my.number.in.range=${random.int[1024,65536]}
+----
+
+The `random.int*` syntax is `OPEN value (,max) CLOSE` where the
+`OPEN,CLOSE` are any character and `value,max` are integers. If
+`max` is provided then `value` is the minimum value and `max` is the
+maximum (exclusive).
+
 [[boot-features-external-config-command-line-args]]
 === Accessing command line properties
 By default `SpringApplication` will convert any command line option arguments (starting
@@ -1538,6 +1556,10 @@ interaction. For Example:
 	}
 ----
 
+To change the port you can add environment properties to
+`@IntegrationTest` as colon- or equals-separated name-value pairs,
+e.g. `@IntegrationTest("server.port:9000")`.
+
 [[boot-features-test-utilities]]
 === Test utilities
 A few test utility classes are packaged as part of `spring-boot` that are generally