changed readme (added velocypack javadoc)

Author: mpv1989

README.md

@@ -133,3 +133,4 @@ ArangoDB arangoDB = new ArangoDB.Builder().registerModule(new VPackJodaModule())
 * [Examples](src/test/java/com/arangodb/example)
 * [Tutorial](https://www.arangodb.com/tutorials/tutorial-sync-java-driver/)
 * [JavaDoc](http://arangodb.github.io/arangodb-java-driver/javadoc-4_1/index.html)
+* [JavaDoc VelocyPack](http://arangodb.github.io/java-velocypack/javadoc-1_0/index.html)