Spring cloud samples (#3010)

* Matchers is now deprecated in Mockito 2, it's now replaced by ArgumentMatchers

* BAEL-1069: Guide to diamond operator in Java

* Changes after review

* BAEL-719: Intro to Spring Cloud Stream

* Pull request changes done

* Renamed unit tests

* Add spring-cloud-stream

* Add module

* Exclude integration tests from spring-cloud

spring-cloud/pom.xml

@@ -1,7 +1,7 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <project xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
-    xmlns="http://maven.apache.org/POM/4.0.0"
-    xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
+         xmlns="http://maven.apache.org/POM/4.0.0"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
     <modelVersion>4.0.0</modelVersion>
 
     <groupId>com.baeldung.spring.cloud</groupId>
@@ -15,8 +15,9 @@
         <module>spring-cloud-ribbon-client</module>
         <module>spring-cloud-rest</module>
         <module>spring-cloud-zookeeper</module>
-		<module>spring-cloud-gateway</module>
-		<module>spring-cloud-connectors-heroku</module>
+        <module>spring-cloud-gateway</module>
+        <module>spring-cloud-stream</module>
+        <module>spring-cloud-connectors-heroku</module>
     </modules>
     <packaging>pom</packaging>
 
@@ -38,6 +39,7 @@
         <spring-cloud-starter-eureka.version>1.2.3.RELEASE</spring-cloud-starter-eureka.version>
         <spring-cloud-starter-feign.version>1.2.3.RELEASE</spring-cloud-starter-feign.version>
         <spring-cloud-starter-hystrix.version>1.2.3.RELEASE</spring-cloud-starter-hystrix.version>
+        <spring-cloud-stream.version>1.3.0.RELEASE</spring-cloud-stream.version>
         <spring-boot-starter-web.version>1.4.2.RELEASE</spring-boot-starter-web.version>
         <maven-compiler-plugin.version>3.6.0</maven-compiler-plugin.version>
         <spring-boot-maven-plugin.version>1.4.2.RELEASE</spring-boot-maven-plugin.version>