Add Automatic-Module-Name manigest entry

For JDK 9 module system interoperability.

Automatic-Module-Name: com.rabbitmq.client

Fixes #320

Author: acogoluegnes

pom.xml

@@ -861,6 +861,9 @@
         <configuration>
           <archive>
             <manifestFile>${project.build.outputDirectory}/META-INF/MANIFEST.MF</manifestFile>
+            <manifestEntries>
+              <Automatic-Module-Name>com.rabbitmq.client</Automatic-Module-Name>
+            </manifestEntries>
           </archive>
         </configuration>
       </plugin>