feat(wrapper): add support for eventbus.send() arg failureHandler

The eventbus of Vert.x 3 add support for an additional argument
`failureHandler`. While this will be not used from this module
(due backwards compatiblity), the wrapper will delegate such argument
blindly.

Relates #42

Author: knalli

src/lib/service/delegate/Live.js

@@ -250,6 +250,7 @@ class LiveDelegate extends BaseDelegate {
           deferred.reject();
         }), timeout, 1);
         // Send message
+        // TODO after dropping support for Vert.x < v3, this can be enriched with failureHandler
         this.eventBus.send(address, message, (reply) => {
           this.$interval.cancel(timer); // because it's resolved
           deferred.resolve(reply);

src/lib/wrapper/Base.js

@@ -10,7 +10,7 @@ class BaseWrapper {
 
   login(username, password, replyHandler) {}
 
-  send(address, message, replyHandler) {}
+  send(address, message, replyHandler, failureHandler) {}
 
   publish(address, message) {  }
 

src/lib/wrapper/Eventbus.js

@@ -236,10 +236,11 @@ class EventbusWrapper extends BaseWrapper {
    * @param {string} address target address
    * @param {object} message payload message
    * @param {function=} replyHandler optional callback
+   * @param {function=} failureHandler optional callback (since Vert.x 3.0.0)
    */
-  send(address, message, replyHandler) {
+  send(address, message, replyHandler, failureHandler) {
     if (this.instance) {
-      this.instance.send(address, message, replyHandler);
+      this.instance.send(address, message, replyHandler, failureHandler);
     }
   }