Nail Maven javadoc plugin version

Dave Syer · Dave Syer · commit 464e38eb7084 · 2014-09-24T15:15:07.000+01:00
diff --git a/pom.xml b/pom.xml
@@ -185,6 +185,7 @@
       </plugin>
       <plugin>
         <artifactId>maven-javadoc-plugin</artifactId>
+        <version>2.9.1</version>
         <executions>
           <execution>
             <id>javadoc</id>
