GH-65: Add polled-consumer Sample

Resolves https://github.com/spring-cloud/spring-cloud-stream-samples/issues/65

Polishing - PR Comments

- add docker-compose
- change runner to process multiple messages

processor-samples/polled-consumer/pom.xml

@@ -0,0 +1,44 @@
+<?xml version="1.0" encoding="UTF-8"?>
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+	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>
+
+	<artifactId>polled-consumer</artifactId>
+	<packaging>jar</packaging>
+
+	<name>polled-consumer</name>
+	<description>Demo project for a polled consumer</description>
+
+	<parent>
+		<groupId>spring.cloud.stream.samples</groupId>
+		<artifactId>spring-cloud-stream-samples-parent</artifactId>
+		<version>0.0.1-SNAPSHOT</version>
+		<relativePath>../..</relativePath>
+	</parent>
+
+	<dependencies>
+		<dependency>
+			<groupId>org.springframework.boot</groupId>
+			<artifactId>spring-boot-starter-test</artifactId>
+			<scope>test</scope>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.cloud</groupId>
+			<artifactId>spring-cloud-stream-binder-kafka</artifactId>
+		</dependency>
+		<dependency>
+			<groupId>org.springframework.kafka</groupId>
+			<artifactId>spring-kafka-test</artifactId>
+		</dependency>
+	</dependencies>
+
+	<build>
+		<plugins>
+			<plugin>
+				<groupId>org.springframework.boot</groupId>
+				<artifactId>spring-boot-maven-plugin</artifactId>
+			</plugin>
+		</plugins>
+	</build>
+
+</project>