Add appendix for 2.1.x kafka-clients jar

Author: garyrussell

src/reference/asciidoc/appendix.adoc

@@ -1,3 +1,53 @@
+[[deps-for-21x]]
+== Override Dependencies to use the 2.1.x kafka-clients with an Embedded Broker
+
+When using `spring-kafka-test` (version 2.2.x) with the 2.1.x `kafka-clients` jar, you will need to override certain transitive dependencies as follows:
+
+[source, xml]
+----
+<dependency>
+    <groupId>org.springframework.kafka</groupId>
+    <artifactId>spring-kafka</artifactId>
+    <version>${spring.kafka.version}</version>
+</dependency>
+
+<dependency>
+    <groupId>org.springframework.kafka</groupId>
+    <artifactId>spring-kafka-test</artifactId>
+    <version>${spring.kafka.version}</version>
+    <scope>test</scope>
+</dependency>
+
+<dependency>
+    <groupId>org.apache.kafka</groupId>
+    <artifactId>kafka-clients</artifactId>
+    <version>2.1.0</version>
+</dependency>
+
+<dependency>
+    <groupId>org.apache.kafka</groupId>
+    <artifactId>kafka-clients</artifactId>
+    <version>2.1.0</version>
+    <classifier>test</classifier>
+</dependency>
+
+<dependency>
+    <groupId>org.apache.kafka</groupId>
+    <artifactId>kafka_2.11</artifactId>
+    <version>2.1.0</version>
+    <scope>test</scope>
+</dependency>
+
+<dependency>
+    <groupId>org.apache.kafka</groupId>
+    <artifactId>kafka_2.11</artifactId>
+    <version>2.1.0</version>
+    <classifier>test</classifier>
+    <scope>test</scope>
+</dependency>
+----
+
+[appendix]
 [[history]]
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