Build javadocs automatically on packaging

Change-Id: I2cab0754b8e87c676f8d36200131ed5c1abf5fa2
diff --git a/pom.xml b/pom.xml
index 21fae85..55ee1d4 100644
--- a/pom.xml
+++ b/pom.xml
@@ -274,6 +274,15 @@
                         </tag>
                     </tags>
                 </configuration>
+                <executions>
+                    <execution>
+                        <id>attach-javadocs</id>
+                        <phase>package</phase>
+                        <goals>
+                            <goal>aggregate-jar</goal>
+                        </goals>
+                    </execution>
+                </executions>
             </plugin>
         </plugins>
     </build>